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Background Non-technical skills (NTS) are integral to team performance and subsequent quality and safety of care. Behavioral marker systems (BMSs) are now increasingly used in healthcare to support the training and assessment of team NTS. Within gastrointestinal endoscopy, this is an area of novel research. The aims of this study were to define the core relevant NTS for endoscopy teams and develop a preliminary framework for a team-based BMS known as TEAM-ENTS (Teamwork in Endoscopy Assessment Module for Endoscopic Non-Technical Skills). Methods This study was conducted in two phases. In phase 1, a literature review of team-based BMSs was performed to inform an interview study of core endoscopy team members. Cognitive task analysis was used to break down the NTS relevant to endoscopy teams. Framework analysis generated the structure for the preliminary TEAM-ENTS framework. In phase 2, a modified Delphi process was undertaken to refine the items of the framework. Results Seven consultant endoscopists and six nurses were interviewed. The final coding framework consisted of 88 codes grouped into five overarching categories. In total, 58 participants were recruited to the Delphi panel. In the first round, nine elements and 37 behavioral descriptors did not meet consensus. Following item adjustment, merging and deletion, all remaining items met consensus thresholds after the second round. The refined TEAM-ENTS BMS consists of five categories, 16 elements, and 47 behavioral descriptors. Conclusions The refined TEAM-ENTS behavioral marker system was developed to reflect the core NTS relevant to endoscopy teams. Future studies will aim to fully validate this tool.

IntroductionThe Joint Advisory Group on Gastrointestinal (GI) Endoscopy (JAG) biennial census provides a unique view of UK endoscopy. The 2021 census was conducted to understand the impact of ongoing pressures, highlighted in the previous census, as well as COVID-19.MethodsThe census was sent to all JAG-registered services in April 2021. Data were analysed across the domains of activity, waiting time targets, workforce, COVID-19, safety, GI bleeding, anaesthetic support, equipment and decontamination. Statistical methods were used to determine associations between domain-specific outcome variables and core demographic data.Results321 services completed the census (79.2% response rate). In the first 3 months of 2021, 57.9% of NHS services met urgent cancer waits, 17.9% met routine waits and 13.4% met surveillance waits. Workforce redeployment was the predominant reason cited for not meeting targets. There were significant regional differences in the proportion of patients waiting 6 or more weeks (p=0.001). During the pandemic, 64.8% of NHS services had staff redeployed and there was a mean sickness rate of 8.5%. Services were, on average, at 79.3% activity compared with 2 years ago. JAG-accredited services are more likely to meet urgent cancer waits, with a lower proportion of patient waiting 6 weeks or more (p=0.03). Over 10% of services stated that equipment shortage interfered with service delivery.ConclusionsServices are adapting to continued pressure and there are signs of a focused response to demand at a time of ongoing uncertainty. This census’ findings will inform ongoing guidance from JAG and relevant stakeholders.

Underperformance can be defined as performance which persistently falls below a desired minimum standard considered acceptable for patient care. Within gastrointestinal endoscopy, underperformance may be multifactorial, related to an individual’s knowledge, skills, attitudes, health or external factors. If left unchecked, underperformance has the potential to impact on care and ultimately patient safety. Managing underperformance should be a key attribute of high-quality endoscopy service, as recognised in the Joint Advisory Group on Gastrointestinal Endoscopy (JAG) accreditation process. However, it is recognised that not all services have robust mechanisms to do this.This article provides the JAG position on managing underperformance in endoscopy, defined through a practical framework. This follows a stepwise process of detecting underperformance, verification, identification of additional causative factors, providing support and reassessment. Detection and verification of issues may require use of multiple evidence sources, including performance data, feedback and appraisal reports. Where technical underperformance is identified, this should be risk stratified by potential risk to patient safety. Support should be tailored to each individual case based on the type of underperformance detected, any causative factors with an action plan developed. Support may include coaching, mentoring, training and upskilling. Wider support from the medical director’s office or external services may also be required. Monitoring and reassessment is a crucial part of the overall process.

Introduction Endoscopy services are expected to meet standards in four domains to achieve JAG accreditation: clinical quality, patient experience, training and workforce. At a JAG assessment, accreditation is ‘deferred’ if the service does not achieve the standards. The aim of this study was to analyse the standards on which NHS and independent sector (IS) services have their accreditation deferred to highlight themes for improvement and identify where support is needed. Methods A retrospective analysis of accreditation assessments from Nov 2016 to Jan 2020 was performed. Services were included if they had a deferral based on one or more standards. Where services had multiple reasons for deferral under one standard, records were de-duplicated. The proportion of deferrals per standard was calculated. Wilcoxon signed-rank test was used to compare deferral proportions between NHS and IS services. Results 276 services underwent assessment, 90 services had reasons for deferral, across 1255 standards. 73% of services included in the analysis were NHS. Table 1 shows the standards that were most and least likely to cause deferral across each domain: When NHS and IS services were compared, there were significant differences for deferral reasons in the clinical quality (p Conclusions This study provides insights into reasons for accreditation deferral between NHS and IS services. There are clear differences with NHS services more likely to defer on patient experience standards and IS services on clinical quality standards. Further work will focus on qualitative studies to investigate these findings further with the aim of supporting services seeking accreditation.

Introduction The Joint Advisory Group on Gastrointestinal endoscopy (JAG) conduct a biennial census to understand factors related to endoscopy quality, workforce and training across services in the UK. The study reports the results of the 2019 census. Methods A census of all UK JAG-registered services was conducted in April 2019. Questions were devised by an expert panel covering domains of activity, workforce and waiting times. Question items were informed by results of the previous census. Results were collated and analysed using Chi Square, Fisher’s exact and Kruskal Wallis tests. Results The response rate was 68.4%. A total of 2,133,541 endoscopic procedures were performed in 2018. In March 2019, 31,938 endoscopy lists were delivered (mean 99.2 ± 95.7 per service). The responding services employed 5,578 endoscopists (mean 17.32 ± 10.13, 12% non-medical), 1,366 trainees (mean 4.24 ± 6.43) and 12,680 nurses and allied health professionals (AHP) (mean 39.94 ± 284.81). There was a nursing and AHP vacancy rate of 7.29%. Region (p = 0.02) and service type (p Out of the lists performed by trainees, 51.9% were for training only. An average of 7.46 (± 1.45) oesophago-gastroduodenoscopies and 3.86 (± 0.85) colonoscopies were booked for each training list. There was a significant regional influence on number of trainee lists (p In the first 3 months of 2019, waiting time targets were met by 73.7% of services for urgent cancer, 68.7% for routine waits and 63.4% for surveillance waits. There was a significant difference in meeting targets between region (p Conclusions This census reflects the most extensive data regarding current UK endoscopy practice. There is evidence of service pressure, affecting wait times and training opportunities with significant regional and service-specific variability.

Introduction The ‘Improving Safety and Reducing Error in Endoscopy’ (ISREE) strategy has highlighted the need to improve our understanding of factors related to safety across UK endoscopy. This study assesses aspects of safety that were included in the Joint Advisory Group on Gastrointestinal endoscopy (JAG) biennial census of services. Methods An expert panel devised questions across 7 themes that complemented JAG safety domains. These were incorporated into the census of UK JAG-registered services in April 2019. Census results were collated and analysed. Categorical data was analysed through Chi square, Fisher’s Exact, Kruskal Wallis and Friedman’s tests. Free text responses were analysed thematically. Results The response rate was 68.4%. Across March 2019, a total of 1535 patient safety incidents (PSIs) were reported (per service mean 4.80, SD 11.87). There was a significant difference in reporting dependent on incident type (p Anaesthetic-supported (AS) lists were unavailable to 27% of services. This varied amongst service type (p The majority of acute services have a gastrointestinal bleed (GIB) service (82.2%) but provision is significantly different between regions (p Overall, 66.1% of services reported having an effective strategy for supporting underperformance. More endoscopists require support for technical skills than non-technical skills (p = 0.001). Simulation provision was 49.1% across acute services, with significant regional differences (p = 0.001). Learning is shared following discussion of adverse events in 94.1% services. Patient feedback is used primarily to support learning, training and quality improvement. Conclusions This is the first survey of national endoscopy safety practice and highlights regional and service-specific variability. These results are important in guiding the ISREE strategy forwards in supporting safer UK endoscopy.

Introduction The National Endoscopy Database (NED) is populated by data extracted automatically from endoscopy reporting systems (ERSs) of endoscopy services in the UK. 406 out of 520 UK endoscopy sites are currently uploading. We aimed to provide an overview of oesophagogastroduodenoscopies (OGDs) stored on NED. Methods Data from all OGDs uploaded to NED from 2016 to the 28th January 2020 was accessed and analysed using the standard output from the NED website. Results 1,010,741 OGDs have been uploaded to NED. 651,270 of those are from 2019, compared to 281,883 in 2018 and 21,457 in 2017, indicating the ongoing roll-out of NED across the UK. 47% of procedures were performed on male patients, 52% on female and 1% unspecified. 27% of OGDs were performed on patients 13% of procedures were on in-patients, 65% on out-patients, while 22% were unspecified. 51% of procedures were routine, 37% urgent, 3% emergency, and 3% surveillance. 7% were not specified. 49% of procedures were unsedated. The most common indications were: Dyspepsia (17%), Heartburn/Reflux (15%), Anaemia (15%), Dysphagia (14%), Abdominal Pain (12%). Other frequent indications were: Weight Loss (7%), Nausea/Vomiting (6%), Melaena (5%), Haematemesis (3%), Barrett’s Oesophagus (3%), Varices Surveillance (2%). ‘Other’ was included in the indication field in 37% of OGDs. The most common diagnoses were: Normal (31%), Hiatus Hernia (27%), Non-erosive Gastritis (17%), Reflux Oesophagitis (11%). Other frequent diagnoses were: Barrett’s oesophagus (7%), Erosive Gastritis (6%), Gastric Polyp(s) (5%), Non-erosive Duodenitis (5%), Oesophageal Varices (2%), Erosive Duodenitis (2%), Duodenal Ulcer (2%), Gastric Ulcer (2%). ‘Other’ was included in the diagnosis field in 18% of OGDs. (NB: Multiple indications and diagnoses can be entered for a procedure, hence sum of percentages is greater than 100% for these categories) Conclusion The majority of procedures were performed in the ≥ 50 age group, peaking between ages 70 to 79, although a quarter of all procedures were performed in people younger than 50. Close to half of OGDs are performed without sedation. Procedure uploads to the NED continue to increase exponentially year on year. The volume of data and high proportion of sites uploading allows unparalleled insights into OGD practice in the UK.

Patient safety incidents (PSIs) are unintended or unexpected incidents which can or do lead to patient harm. The Joint Advisory Group on Gastrointestinal Endoscopy (JAG) acknowledges that PSIs should be reviewed by endoscopy services and learning shared among staff. It is recognised that more could be done to promote shared learning as outlined by the JAG ‘Improving Safety and Reducing Error in Endoscopy’ strategy. The ‘Case of the month’ series aims to provide a broad selection of cases and subsequent learning that can be shared among services and their workforce. This review focuses on five case vignettes that highlight a variety of PSIs in endoscopy. A structured approach, based on incident analysis methodology, is applied to each case to categorise PSIs and develop learning points. Learning is directed toward the individual, team and healthcare organisation. A selection of methods to disseminate learning at local, regional and national levels are also described.

Background Endoscopy services have had to rapidly adapt their working practices in response to COVID-19. As recovery of endoscopy services proceeds, our workforce faces numerous challenges that can impair effective teamworking. We designed and developed a novel toolkit to support teamworking in endoscopy during the pandemic. Methods A human factors model was developed to understand the impact of COVID-19 on endoscopy teams. From this, we identified a set of key teamworking goals, which informed the development of a toolkit to support several team processes. The toolkit was refined following expert input and refinement over a 6-week period. Results The toolkit consists of four cognitive aids that can be used to support team huddles, briefings, and debriefs, alongside techniques to optimize endoscopic nontechnical skills across the patient-procedure pathway. We describe the processes that local endoscopy units can employ to implement this toolkit. Conclusion A toolkit of cognitive aids, based on human factors principles, may be useful in supporting teams, helping them adapt to working safely in the era of COVID-19.

IntroductionThe COVID-19 pandemic has profoundly affected UK endoscopy workload. The Joint Advisory Group on GI endoscopy and British Society of Gastroenterology issued guidelines on endoscopy service delivery changes and restoration. We surveyed UK endoscopy clinical leads to gain insights into service restoration.MethodsA Google Forms-designed survey, assessing endoscopy provision, Covid minimisation and referral pathways was circulated to all UK endoscopy leads. The survey was open between 19 and 24 May 2020.Results97 endoscopy leads completed the survey, with all UK nations and regions represented. Analysis showed 20% of endoscopy services were not providing endoscopy. Workload limitations were due to enforced interprocedural downtime (92%; with some services enforcing >1-hour downtime between procedures), social distancing (88%) and working in personal protective equipment (PPE) (87%). 91% of services reported a referral backlog (urgent median 2 months, routine median 6 months). 96% of services reported no current problems accessing PPE. Level 1/2 PPE use in colonoscopy was not uniform. 63% of services routinely swab patients for COVID-19 before endoscopy, 88% of services do not routinely swab asymptomatic staff. Comments addressed reducing endoscopy demand through vetting and changing referral criteria, the mostly commonly cited strategy being increased faecal immunochemical testing in symptomatic patients (70% of services).ConclusionThis survey demonstrates the pandemic’s profound impact on UK endoscopy. Challenges include standardising Covid-minimisation strategies and recovering staffing levels. To improve endoscopy services, there is a need to refine referral pathways, improve vetting and clarify guidance on downtime and PPE within endoscopy.

BackgroundThe Joint Advisory Group on Gastrointestinal Endoscopy (JAG) ‘Improving Safety and Reducing Error in Endoscopy’ (ISREE) strategy was developed in 2018. In line with the strategy, a survey was conducted within the JAG census in 2019 to gain further insights and understanding of key safety-related areas within UK endoscopy.MethodsQuestions were developed using the ISREE strategy as a guide and adapted by key JAG stakeholders. They were incorporated into the 2019 JAG census of UK endoscopy services. Quantitative and qualitative statistical methods were employed to analyse the results.ResultsThere was a 68% response rate. There was regional variability in the provision of out-of-hours GIB services (pConclusionsThe census provides a benchmark for key safety-related characteristics of endoscopy services. These results have highlighted key areas to develop, guided by the ISREE strategy.

IntroductionThe 2017 Joint Advisory Group on Gastrointestinal (GI) Endoscopy (JAG) census highlighted the pressure endoscopy services were under in meeting national targets and the factors behind this. In 2019, JAG conducted a further national census of endoscopy services to understand trends in activity, workforce and waiting time targets.MethodsIn April 2019, the census was sent to all eligible JAG-registered services. Collated data were analysed through various statistical methods. A further comparative dataset was created using available submissions from the 2017 census matched to services in the current census.ResultsThere was a 68% response rate (322/471). There has been a 12%–15% increase in activity across all GI procedures with largest increases in bowel cancer screening. Fewer services are meeting waiting time targets compared with 2017, with endoscopist, nursing and physical capacity cited as the main reasons. Services are striving to improve capacity: 80% of services have an agreed business plan to meet capacity and the number using insourcing has increased from 13% to 20%. The workforce has increased, with endoscopist numbers increasing by 15%, nurses and allied health professionals by 14% and clerical staff by 30%.ConclusionsThe 2019 JAG census is the most recent and extensive survey of UK endoscopy services. There is a clear trend of increasing activity with fewer services able to meet national waiting time targets than 2 years ago. Services have increased their workforce and improved planning to stem the tide but there remains a continued pressure to deliver high quality, safe endoscopy. In light of the COVID-19 pandemic, JAG recognises that these pressures will be severely exacerbated and waiting time targets for accreditation will need adjustment and tolerance during the evolution and recovery from the pandemic.

Hexagonal boron nitride (hBN) is an emerging layered material that plays a key role in a variety of two-dimensional devices, and has potential applications in nanophotonics and nanomechanics. Here, we demonstrate the first cavity optomechanical system incorporating hBN. Nanomechanical resonators consisting of hBN beams with predicted thickness between 8 nm and 51 nm were fabricated using electron beam induced etching and positioned in the optical nearfield of silicon microdisk cavities. A 160 fm/$\sqrt{\text{Hz}}$ sensitivity to the hBN nanobeam motion is demonstrated, allowing observation of thermally driven mechanical resonances with frequencies between 1 and 23 MHz, and mechanical quality factors reaching 1100 at room temperature in high vacuum. In addition, the role of air damping is studied via pressure dependent measurements. Our results constitute an important step towards realizing integrated optomechanical circuits employing hBN., Comment: Revised version

Editorial by Chris Healey and Katrina Schlunke.

Introduction A higher proportion of chronic mental illness is reported for populations residing in inner and outer regional (IOR) areas when compared to major cities in Australia. Conversely, fewer mental health professionals work in IOR areas when compared to major cities indicating poorer access to services for rural populations. Rural emergency departments (EDs) and urgent care centres (UCCs) deliver a broad range of services. Often they are the first point of care for consumers experiencing acute mental health issues. Rural nurses working in EDs and UCCs require a diverse clinical skill set to manage complex presentations, often with limited support and resources. Developments in telehealth services have reportedly improved access for rural consumers. It is known that nurses report a lack of skills and confidence when managing mental health presentations. Despite these challenges, there is little documented regarding the experience of generalist nurses managing acute mental health presentations in rural hospitals that have limited support of community mental health teams and no onsite inpatient mental health facilities. Methods A qualitative study was conducted to explore the experience of rural nurses in managing acute mental health presentations within an emergency context. An interview guide developed from the literature was used to explore issues of experience, safety, knowledge and clinical confidence. Thirteen rural generalist nurses from one rural emergency department and two rural UCCs located in south-west Victoria participated in a semi-structured interview. Interviews were audio-recorded and transcribed verbatim. Transcriptions were thematically analysed by applying an inductive descriptive approach. Results The majority of participants were experienced generalist registered nurses with no formal qualifications in mental health. Two participants had some clinical experience in mental health and drug and alcohol. Themes elicited from data analysis and discussion between the researchers were (1) 'we are the frontline', (2) 'doing our best to provide care', (3) 'complexities of navigating the system', and (4) 'thinking about change'. Findings indicated that rural generalist nurses deliver the majority of care to mental health consumers in EDs and UCCs. Local mental health clinicians and emergency service providers offer limited support, with a reliance on telephone triage for after-hours assessment. Multiple challenges were cited including coordinating the transfer of consumers to inpatient facilities and feeling inadequately supported. Irrespective of these challenges, nurses reported delivering the best possible care to consumers despite reporting a lack of knowledge and skills. Recommendations for improving the delivery of care included increasing access to emergency mental health training and receiving more support from local mental health teams. The need for more rural mental health facilities was also discussed. Conclusions The findings from this study suggest generalist nurses are the frontline providers of care for mental health consumers in rural EDs and UCCs. Nurses feel ill-equipped for assessing and managing mental health presentations, relying heavily on local mental health teams and telephone triage who provide limited onsite support. The need to support nurses through training and mentoring relationships with community mental health teams is highlighted by this study in conjunction with improving the delivery of mental health services in rural areas.

Background: Treatment guidelines recommend a stepwise approach to primary biliary cholangitis: all patients begin treatment with ursodeoxycholic acid (UDCA) monotherapy and those with an inadequate biochemical response after 12 months are subsequently considered for second-line therapies. However, as a result, patients at the highest risk can wait the longest for effective treatment. We determined whether UDCA response can be accurately predicted using pretreatment clinical parameters. Methods: We did logistic regression analysis of pretreatment variables in a discovery cohort of patients in the UK with primary biliary cholangitis to derive the best-fitting model of UDCA response, defined as alkaline phosphatase less than 1·67 times the upper limit of normal (ULN), measured after 12 months of treatment with UDCA. We validated the model in an external cohort of patients with primary biliary cholangitis and treated with UDCA in Italy. Additionally, we assessed correlations between model predictions and key histological features, such as biliary injury and fibrosis, on liver biopsy samples. Findings: 2703 participants diagnosed with primary biliary cholangitis between Jan 1, 1998, and May 31, 2015, were included in the UK-PBC cohort for derivation of the model. The following pretreatment parameters were associated with lower probability of UDCA response: higher alkaline phosphatase concentration (p

We present the design, fabrication and initial characterization of a paddle nanocavity consisting of a suspended sub-picogram nanomechanical resonator optomechanically coupled to a photonic crystal nanocavity. The optical and mechanical properties of the paddle nanocavity can be systematically designed and optimized, and key characteristics including mechanical frequency easily tailored. Measurements under ambient conditions of a silicon paddle nanocavity demonstrate an optical mode with quality factor $Q_o$ ~ 6000 near 1550 nm, and optomechanical coupling to several mechanical resonances with frequencies $\omega_m/2\pi$ ~ 12-64 MHz, effective masses $m_\text{eff}$ ~ 350-650 fg, and mechanical quality factors $Q_m$ ~ 44-327. Paddle nanocavities are promising for optomechanical sensing and nonlinear optomechanics experiments., Comment: 5 pages, 4 figures

Nonlinear cavity optomechanics is a promising platform for realizing experiments which reveal the quantum properties of nanomechanical structures. Here we introduce an optomechanical system combining strong nonlinear optomechanical coupling, low mass and large optical mode spacing. This nanoscale “paddle nanocavity” supports mechanical resonances with hundreds of fg mass which couple nonlinearly to optical modes with a single photon quadratic optomechanical coupling rate that is four orders of magnitude higher than competing systems. This coupling relies on strong interactions between the nanocavity optical field and mechanical excitations in a structure whose optical mode spectrum is highly non-degenerate. Nonlinear optomechanical readout of thermally driven motion in these devices should be observable for temperatures above 50 mK, and measurement of phonon shot noise is achievable. This work shows that strong nonlinear effects can be realized without relying on coupling between nearly degenerate optical modes, thus avoiding parasitic linear coupling present in two mode systems.

Nonlinear optomechanical coupling is the basis for many potential future experiments in quantum optomechanics (e.g., quantum non-demolition measurements, preparation of non-classical states), which to date have been difficult to realize due to small non-linearity in typical optomechanical devices. Here we introduce an optomechanical system combining strong nonlinear optomechanical coupling, low mass and large optical mode spacing. This nanoscale "paddle nanocavity" supports mechanical resonances with hundreds of fg mass which couple nonlinearly to optical modes with a quadratic optomechanical coupling coefficient $g^{(2)} > 2\pi\times400$ MHz/nm$^2$, and a two phonon to single photon optomechanical coupling rate $\Delta \omega_0 > 2\pi\times 16$ Hz. This coupling relies on strong phonon-photon interactions in a structure whose optical mode spectrum is highly non--degenerate. Nonlinear optomechanical readout of thermally driven motion in these devices should be observable for T $> 50 $ mK, and measurement of phonon shot noise is achievable. This shows that strong nonlinear effects can be realized without relying on coupling between nearly degenerate optical modes, thus avoiding parasitic linear coupling present in two mode systems., Comment: 8 pages, 5 figures

Cost containment in prescribing budgets is, and always will be, a key priority in any health service with limited resources. Therefore, a number of primary care trusts (PCT) have recently initiated pharmacy-led switches of 5-aminosalicylic acids (5-ASAs), with the intention of reducing prescribing budgets. However, this has generated considerable controversy among gastroenterologists, as there is concern that the clinical consequences of such programmes have not been adequately explored. PCTs are currently under no obligation to consult secondary care prior to initiating pharmacy-led switches. In a secondary care-led condition such as inflammatory bowel disease (IBD), this seems highly counterintuitive. If gastroenterologists were to be consulted, how would we respond, and what could we contribute? This article examines the clinical consequences of PCT-initiated switch programmes in IBD, and the knock-on effects on patients and the secondary care gastroenterology community. For a switch programme to be justified, the financial benefits it imparts must be balanced against its clinical effects. Here, we consider what the clinical effects of a 5-ASA switch might be. Many gastroenterologists express concern over such programmes, but is there evidence for a detrimental effect, and what is the experience that exists among the secondary care community to inform our approach? Many gastroenterology specialists have already encountered pharmacy-led switches firsthand, and some of their experiences provide immediate cause for concern. Although anecdotal, reports abound that 5-ASA switches have been followed by flares of active disease and other adverse effects in a worrying number of patients. For example, in one recent pharmacy-led switch programme, a patient showed a significant drop in his white blood cell count after his 5-ASA was changed, and another two patients experienced bouts of diarrhoea. In a particularly worrying case, a young woman who was very concerned about her 5-ASA being switched was subsequently admitted with an episode …

Dissipative and dispersive optomechanical couplings are experimentally observed in a photonic crystal split-beam nanocavity optimized for detecting nanoscale sources of torque. Dissipative coupling of up to approximately $500$ MHz/nm and dispersive coupling of $2$ GHz/nm enable measurements of sub-pg torsional and cantilever-like mechanical resonances with a thermally-limited torque detection sensitivity of 1.2$\times 10^{-20} \text{N} \, \text{m}/\sqrt{\text{Hz}}$ in ambient conditions and 1.3$\times 10^{-21} \text{N} \, \text{m}/\sqrt{\text{Hz}}$ in low vacuum. Interference between optomechanical coupling mechanisms is observed to enhance detection sensitivity and generate a mechanical-mode-dependent optomechanical wavelength response., Comment: 11 pages, 6 figures

We demonstrate a scalable process flow to fabricate three-dimensional free-standing devices from bulk single-crystal diamond. Using a dimpled fiber taper, we couple selectively to four mechanical modes of a nanobeam to measure its optomechanical response.

Optomechanical nanocavities allow nanomechanical resonances to be measured optically with high sensitivity. We have created a new type of photonic crystal nanocavity optomechanical sensor optimized for detecting sources of torque and other forces which can deflect nanoscale cantilevers. This nanocavity consists of two precisely engineered photonic Bragg mirrors patterned in silicon cantilevers and separated by a 50-100 nm wide gap. Simulations of the optical and mechanical modes predict that mechanical displacements of the sub-picogram cantilevers will shift the optical nanocavity resonance frequency at a rate exceeding 20 GHz / nm, and that the nanocavity optical mode may have a quality factor Qo > 10⁶in optimized devices., 13th International Conference on Numerical Simulation of Optoelectronic Devices, NUSOD 2013, August 19-22, 2013, Vancouver, BC, Canada, Series: Proceedings of the ... International Conference on Numerical Simulation of Optoelectronic Devices

Laser Resonators, Microresonators, and Beam Control XV, February 3-7, 2013, San Francisco, CA, USA, Series: Proceedings of SPIE

An optical fiber taper placed in the near field of a "split-beam" photonic crystal nanobeam cavity with a physical gap at the cavity center breaks the system's vertical dielectric symmetry, enabling selective optomechanical coupling to multiple cantilever resonances using a single optical nanocavity mode. © 2013 Optical Society of America., CLEO: QELS_Fundamental Science, CLEO:QELS FS 2013, June 9-14, 2013, San Jose, CA, USA