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Your search keyword '"Andreasson, Joakim"' showing total 32 results
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32 results on '"Andreasson, Joakim"'

1. Ultrafast collapse of molecular polaritons in photoswitch-nanoantennas at room temperature

Author

Kuttruff, Joel, Romanelli, Marco, Pedrueza-Villalmanzo, Esteban, Allerbeck, Jonas, Fregoni, Jacopo, Saavedra-Becerril, Valeria, Andréasson, Joakim, Brida, Daniele, Dmitriev, Alexandre, Corni, Stefano, and Maccaferri, Nicolò

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics, Physics - Optics
Abstract

Molecular polaritons are hybrid light-matter states that emerge when a molecular transition strongly interacts with photons in a resonator. At optical frequencies, this interaction unlocks a way to explore and control new chemical phenomena at the nanoscale. Achieving such a control at ultrafast timescales, however, is an outstanding challenge, as it requires a deep understanding of the dynamics of the collectively coupled molecular excitation and the nanoconfined electromagnetic fields. Here, we investigate the dynamics of collective polariton states, realized by coupling molecular photoswitches to optically anisotropic plasmonic nanoantennas. Pump-probe experiments reveal an ultrafast collapse of polaritons to a single-molecule transition triggered by femtosecond-pulse excitation at room-temperature. Through a synergistic combination of experiments and quantum mechanical modelling, we show that the response of the system is governed by intramolecular dynamics, occurring one order of magnitude faster with respect to the unperturbed excited molecule relaxation to the ground state.

Published
2022
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6. Ultrafast Dynamics of Molecular Polaritons in Photoswitch Nanoantennas

Author

Kuttruff, Joel, primary, Romanelli, Marco, additional, Pedrueza-Villalmanzo, Esteban, additional, Allerbeck, Jonas, additional, Fregoni, Jacopo, additional, Saavedra-Becerril, Valeria, additional, Andreasson, Joakim, additional, Brida, Daniele, additional, Dmitriev, Alexandre, additional, Corni, Stefano, additional, and Maccaferri, Nicolò, additional

Published
2023
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7. Ultrafast Dynamics of Photochromic Molecules Coupled to Anisotropic Plasmon Nanoantennas

Author

Kuttruff, Joel, Romanelli, Marco, Pedrueza-Villalmanzo, Esteban, Allerbeck, Jonas, Fregoni, Jacopo, Saavedra-Becerril, Valeria, Andreasson, Joakim, Brida, Daniele, Dmitriev, Alexandre, Corni, Stefano, Maccaferri, Nicolò, Kuttruff, Joel, Romanelli, Marco, Pedrueza-Villalmanzo, Esteban, Allerbeck, Jonas, Fregoni, Jacopo, Saavedra-Becerril, Valeria, Andreasson, Joakim, Brida, Daniele, Dmitriev, Alexandre, Corni, Stefano, and Maccaferri, Nicolò

Abstract

We study coupling of merocyanine to aluminum nanoantennas in weak and strong interaction regimes. Experiments reveal modification of the molecular dynamics induced by the plasmons as verified by quantum modelling of the hybrid system.

Published
2022
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11. Energy and photoinduced electron transfer in a wheel-shaped artificial photosynthetic antenna-reaction center complex

Author

Kodis, Gerdenis, Hambourger, Michael, Terazono, Yuichi, Moore, Thomas A., Liddell, Paul A., Moore, Ana L., Andreasson, Joakim, Gust, Devens, and Garg, Vikas

Subjects
Electron transport -- Research, Porphyrins -- Atomic properties, Porphyrins -- Chemical properties, Chemistry
Abstract

Artificial, functional mimics of a photosynthetic antenna-reaction center complex comprising of five bis-(phenylethynyl) anthracene antenna moieties and a porphyrin-fullerene dyad organized by a central hexaphenylbenzene core are prepared and studied. Observations reveal that the molecules successfully integrate singlet-singlet energy transfer and photoinduced electron transfer.

Published
2006

12. Photochromic control of photoinduced electron transfer. Molecular double-throw switch

Author

Straight, Stephen D., Andreasson, Joakim, Moore, Ana L., Moore, Thomas A., Kodis, Gerdenis, and Gust, Devens

Subjects
Porphyrins -- Electric properties, Isomerization -- Research, Electron transport -- Research, Chemistry
Abstract

A molecular double-throw switch that employs a photochromic moiety to direct photoinduced electron transfer from an excited state donor down either of two pathways was prepared. It was found that photoinduced charge separation originating from the porphyrin is reversibly directed down either of two different pathways by photoisomerization of the dinydroindolizine.

Published
2005

13. Photoinduced hole transfer from the triplet state in a porphyrin-based donar-bridge-acceptor system

Author

Andreasson, Joakim, Gust, Devens, Moore, Ana L., Moore, Thomas A., Kodis,Gerdenis, Martensson, Jerker, Ljungdahl, Thomas, and Bo Albinsson

Subjects
Gold -- Research, Gold -- Chemical properties, Chromophores -- Chemical properties, Porphyrins -- Research, Porphyrins -- Chemical properties, Chemicals, plastics and rubber industries
Abstract

The studies were conducted to investigate the triplet excited-state deactivation of a gold porphyrin (AuP) in porphyrin-based donar-bridge-acceptor (D-B-A) systems. The results show that quenching of (super 3) AuP occurs with high efficiency in the dimers that were connected by fully conjugated budging chromophores, whereas no quenching was observed when the conjugation of the bridge was broken.

Published
2003

14. The photophysical properties of the adenine chromophore

Author

Andreasson, Joakim, Holmen, Anders, and Albinsson, Bo

Subjects
Adenylic acid -- Research, Chemicals, plastics and rubber industries
Abstract

A solvatochromic study in which the energy of the excited states of N6,N6-dimethyl-9-ethyladenine are analyzed as a function of solvent polarity is presented. Attention is given to the link between the formation of the A-state and nonradiative deactivation of the primary excited state for adenine derivatives.

Published
1999

15. A Fluorescent Kinase Inhibitor that Exhibits Diagnostic Changes in Emission upon Binding

Author

Fleming, Cassandra L., Sandoz, Patrick A., Inghardt, Tord, Önfelt, Björn, Grotli, Morten, Andreasson, Joakim, Fleming, Cassandra L., Sandoz, Patrick A., Inghardt, Tord, Önfelt, Björn, Grotli, Morten, and Andreasson, Joakim

Abstract

The development of a fluorescent LCK inhibitor that exhibits favourable solvatochromic properties upon binding the kinase is described. Fluorescent properties were realised through the inclusion of a prodan-derived fluorophore into the pharmacophore of an ATP-competitive kinase inhibitor. Fluorescence titration experiments demonstrate the solvatochromic properties of the inhibitor, in which dramatic increase in emission intensity and hypsochromic shift in emission maxima are clearly observed upon binding LCK. Microscopy experiments in cellular contexts together with flow cytometry show that the fluorescence intensity of the inhibitor correlates with the LCK concentration. Furthermore, multiphoton microscopy experiments demonstrate both the rapid cellular uptake of the inhibitor and that the two-photon cross section of the inhibitor is amenable for excitation at 700 nm., QC 20191002

Published
2019
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16. Elucidating DNA binding of dithienylethenes from molecular dynamics and dichroism spectra

Author

Linares, Mathieu, Sun, Haofan, Biler, Michal, Andreasson, Joakim, Norman, Patrick, Linares, Mathieu, Sun, Haofan, Biler, Michal, Andreasson, Joakim, and Norman, Patrick

Abstract

DNA binding modes of the stereoisomeric rotamers of two dithenylethene derivatives (DTE1 and DTE2) representing candidate molecular photoswitches of great promise for photopharmacology and nanotechnology have been identified and characterized in terms of their binding energies and electronic circular dichroism (CD) responses. In the open form, two binding modes are identified namely minor-groove binding of the lowest-energy conformer with an anti-parallel arrangement of methyl groups and major-groove double-intercalation of the P-enantiomers of an intermediate-state rotamer. Only the latter binding mode is found to be enantiomerically selective and expected to have an overall negative linear dichroism (LD) as observed in the experiment for DTE1 (Angew. Chem., Int. Ed., 2013, 52, 4393). In the closed form, the most favorable binding mode is found to be minor groove binding. Also this binding mode is found to be enantiomerically selective and for DTE1, it is the M-enantiomer that binds the strongest, showing a positive theoretical signature CD band in the long wavelength region with origin in pyridinium ligands. The theoretical CD spectrum is found to be in good agreement with the experimental one, which provides an indirect evidence for a correct identification of the binding mode in the closed form., QC 20190326

Published
2019
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17. Photonic control of photoinduced electron transfer via switching of redox potentials in a photochromic moiety

Author

Terazono, Yuichi ; Terazono, Gerdenis Ko, Andreasson, Joakim ; Jeong, Goojin ;, Brune, Alicia ; Hartmann, Thomas ;, Durr, Heinz ; Durr, Ana L.Moore;, and Moore, Thomas A.; Gust, Devens

Subjects
Complex compounds -- Research, Complex compounds -- Chemical properties, Coordination compounds -- Research, Coordination compounds -- Chemical properties, Porphyrins -- Research, Porphyrins -- Chemical properties, Photochromic materials -- Research, Photochromic materials -- Usage, Chemicals, plastics and rubber industries
Abstract

Use of photochromic effect to control reduction potential of an electron acceptor for photoinduced electron transfer from a covalently linked donor moiety is studied. Switching behavior is reported to occur only when photochromic moiety is exchangeable between a state bound to the porphyrin and a state free solution.

Published
2004

19. Electrical detection of amine ligation to a metalloporphyrin via a hybrid SOI-MOSFET

Author

Takulapalli, Bharath R., Laws, Gez M., Liddell, Paul A., Andreasson, Joakim, Erno, Zach, Gust, Devens, and Thornton, Trevor J.

Subjects
Metal oxide semiconductor field effect transistors -- Design and construction, Monomolecular films -- Analysis, Porphyrins -- Chemical properties, Zinc -- Chemical properties, Chemistry
Abstract

A back-gated silicon-on-insulator metal-oxide-semiconductor field effect transistor (SOI-MOSFET) transistor having a thin native layer of oxide on the top is used, upon which a single monolayer of zinc tetraarylporphyrin is deposited by using Langmuir-Blodgett (LB) methods. The transistor response to a few hundred attomoles of bound pyridine is detected, which when coupled with the ability to reset the device using light has shown that these systems can be used as sensors.

Published
2008

20. All-photonic molecular half-adder

Author

Andreasson, Joakim, Gervaldo, Miguel, Albinson, Bo, Moore, Thomas A., Kodis, Gerdenis, Choong-Do Park, Hambourger, Michael, and Straight, Stephen D.

Subjects
Absorption spectra -- Analysis, Fluorescence -- Analysis, Chemistry
Abstract

The triad successfully demonstrates the function of a molecular half-adder which is simple to operate and cycled many times when one molecule acts as both an AND and an XOR Boolean logic gate that share the same two photonic inputs. The AND function is based on absorption properties of the molecule whereas the XOR function is based on an off-on-off response of the fluorescence to the inputs that results from interchromophore excited-state quenching interaction.

Published
2006

21. Molecular AND and INHIBIT gates based on control of porphyrin fluorescence by photochromes

Author

Straight, Stephen D., Andreasson, Joakim, Moore, Thomas A., Kodis, Gerdenis, Moore, Ana L., Bandyopadhyay, Subhajit, Gust, Devens, and Mitchell, Reginald H.

Subjects
Photochromic materials -- Chemical properties, Photochromic materials -- Research, Porphyrins -- Chemical properties, Porphyrins -- Research, Chemistry
Abstract

A molecular triad consisting of a porphyrin (P) covalently linked to two photochromes, one from the dihydroindolizine family (DHI) and one fro the dihydropyrene family (DHP), is synthesized and found to act as either a molecular AND logic gate or an INHIBIT gate, depending on the inputs and intial state of the photochromes. Independent isomerization of the attached photochromes occurs making it possible to switch porphyrin fluorescence on or off by isomerization of the photochromes.

Published
2005

22. Triplet photophysics of gold(III) porphyrins

Author

Eng, Mattias P., Ljungdahl, Thomas, Andreasson, Joakim, Martensson, Jerker, and Albinsson, Bo

Subjects
Density functionals -- Usage, Porphyrins -- Chemical properties, Gold compounds -- Chemical properties, Chemicals, plastics and rubber industries
Abstract

An investigation of the photophysics of gold(III) porphyrins with steady state and time-resolved spectroscopic methods as well as DFT calculations is presented. The result suggests a short-lived state, with a lifetime of about 20-50 ns in rigid media that is an intermediate between the first excited singlet state and the triplet manifold and acts as a gatekeeper state for formation of the triplets.

Published
2005

23. Photonic switching of photoinduced electron transfer in a dihydropyrene-porphyrin-fullerene molecular triad

Author

Liddell, Paul A., Kodis, Gerenis, Andreasson, Joakim, Garza, Linda de la, and Bandyopadhyay, Subhajit; Mitchell, Reginald H.; Moore, Thomas A.; Moore, Ana L.; Gust, Devens

Subjects
Organic photochemistry -- Research, Porphyrins -- Research, Porphyrins -- Spectra, Chemistry
Abstract

An investigation of photonic control of photoinduced electron transfer, based on a dimethyldihydropyrene (DHP) porphyrin (P) fullerene (C60) molecular traid, is presented. The DHP form of the triad porphyrin excitation leads to formation of a DHP-P(super .+)-C60- state with a quantum yield of ninety-eight percent.

Published
2004

24. Molecules with a sense of logic: a progress report

Author

Andreasson, Joakim and Pischel, U.

Subjects
Chemical Sciences, Hardware_LOGICDESIGN
Abstract

In this tutorial review, the most recent developments in the field of molecular logic and information processing are discussed. Special emphasis is given to the report of progress in the concatenation of molecular logic devices and switches, the design of memory systems working according to the principles of sequential logic, the mimicking of transistors, and the research on photochromic platforms with an unprecedented degree of functional integration. Furthermore, a series of achievements that add up to the conceptual diversity of molecular logic is introduced, such as the realization of highly complex and logically reversible Toffoli and Fredkin gates by the action of DNAzymes or the use of a multifluorophoric platform as a viable approach towards keypad lock functions.

Published
2015

25. Efficient non-radiative deactivation and conformational flexibility of meso-diaryloctaalkylporphyrins in the excited triplet state

Author

Andreasson, Joakim, Zetterqvist, Hanna, Kajanus, Johan, Martensson, Jerker, and Albinsson, Bo

Subjects
Phosphorescence -- Observations, Zinc -- Research, Porphyrins -- Research, Chemicals, plastics and rubber industries
Abstract

The exited triplet state deactivation of zinc(II) meso-diaryloctaalkylporphyins (ZnDAOAP) has been studied over a wide temperature range using triplet- triplet absorption spectroscopy together with steady-state and time-resolved phosphorescence techniques. The triplet species have a 'mother -daughter' relationship and the ground state recovery at room temperature is governed exclusively by a route via the daughter state, as the direct intersystem crossing from the mother state is slow.

Published
2000

26. Storage and Processing of Information Using Molecules: The All-Photonic Approach with Simple and Multi-Photochromic Switches

Author

Andreasson, Joakim and Pischel, U.

Subjects
system, electron-transfer, photochromism, Physical Chemistry, nondestructive, switches, memory, molecular devices, unimolecular platform, logic gates, keypad lock, half-adder, readout, d-flip-flop, fluorescence, logic gate
Abstract

The use of photochromes for the implementation of molecular logic operations is a very promising approach toward molecular computing. This statement is based on a) the possibility of operating such molecular devices exclusively with photonic signals and b) spatiotemporally and remotely controlled switching, which is characteristic for photochromes. Herein, a brief overview of the application of simple photochromes and multi-photochromic conjugates for the small-scale functional integration of complicated logic circuits is given. This complements and extends efforts to design molecular photochromic memories for data storage described by many research groups worldwide.

Published
2013

27. Information Processing with Molecules-Quo Vadis?

Author

Pischel, U., Andreasson, Joakim, Gust, D., and Pais, V. F.

Subjects
materials science, encoder-decoder, quantum dots, silica nanoparticles, photochromism, Physical Chemistry, chemical logic gates, molecular devices, flip-flop, unimolecular platform, drug delivery, keypad lock, half-adder, fluorescence, reversible logic, fluorescence modulation
Abstract

Information processing at the molecular level is coming of age. Since the first molecular AND gate was proposed about 20 years ago, the molecular interpretation of binary logic has become vastly more sophisticated and complex. However, the field is also at a crossroads. While cleverly designed molecular building blocks are abundant, difficult questions remain. How can molecular components be flexibly assembled into larger circuits, and how can these components communicate with one another. The concept of all-photonic switching with photochromic supermolecules has shown some interesting potential and is discussed in this review. Although the field of molecular logic was originally discussed mainly in terms of a technology that might compete with solid-state computers, potential applications have expanded to include clever molecular systems and materials for drug delivery, sensing, probing, encoding, and diagnostics. These upcoming trends, which are herein illustrated by selected examples, deserve general attention.

Published
2013

28. Acid/Base Switching of the Tautomerism and Conformation of a Dioxoporphyrin for Integrated Binary Subtraction

Author

Ding, Yubin, Li, Xin, Hill, Jonathan P., Ariga, Katsuhiko, Ågren, Hans, Andreasson, Joakim, Zhu, Weihong, Tian, He, Xie, Yongshu, Ding, Yubin, Li, Xin, Hill, Jonathan P., Ariga, Katsuhiko, Ågren, Hans, Andreasson, Joakim, Zhu, Weihong, Tian, He, and Xie, Yongshu

Abstract

Compared with most of the reported logic devices based on the supramolecular approach, systems based on individual molecules can avoid challenging construction requirements. Herein, a novel dioxoporphyrin DPH22 was synthesized and two of its tautomers were characterized by single-crystal X-ray diffraction studies. Compound DPH22 exhibits multichannel controllable stepwise tautomerization, protonation, and deprotonation processes through interactions with H and F- ions. By using the addition of H+ and F- ions as inputs and UVNis absorption values at.1=412, 510, 562, and 603 nm as outputs, the controlled tautomerism of DPH22 has been successfully used for the construction of an integrated molecular level half-subtractor and comparator. In addition, this acid/base-switched tautomerism is reversible, thus endowing the system with ease of reset and recycling; consequently, there is no need to modulate complicated intermolecular interactions and electron-/chargetransfer processes., QC 20141105

Published
2014
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30. Light-induced cytotoxicity of a photochromic spiropyran

Author

Nilsson, Jesper R., Li, Shiming, Önfelt, Björn, Andreasson, Joakim, Nilsson, Jesper R., Li, Shiming, Önfelt, Björn, and Andreasson, Joakim

Abstract

In this work we present a novel water soluble spiropyran photoswitch that can be photonically activated inside live cells from a form that has no significant effect on the cellular survival to a form that induces a dramatic toxic response., QC 20111028

Published
2011
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