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Radio-frequency reflectometry allows for fast and sensitive electrical readout of charge and spin qubits hosted in quantum dot devices coupled to resonant circuits. Optimizing readout, however, requires frequency tuning of the resonators and impedance matching. This is difficult to achieve using conventional semiconductor or ferroelectric-based varactors in the detection circuit as their performance degrades significantly in the mK temperature range relevant for solid-state quantum devices. Here we explore a different type of material, strontium titanate, a quantum paraelectric with exceptionally large field-tunable permittivity at low temperatures. Using strontium titanate varactors we demonstrate perfect impedance matching and resonator frequency tuning at 6 mK and characterize the varactors at this temperature in terms of their capacitance tunability, dissipative losses and magnetic field sensitivity. We show that this allows us to optimize the radio-frequency readout signal-to-noise ratio of carbon nanotube quantum dot devices to achieve a charge sensitivity of 4.8 $\mu$e/Hz$^{1/2}$ and capacitance sensitivity of 0.04 aF/Hz$^{1/2}$.

Since the introduction of bolometers more than a century ago, they have been applied in a broad spectrum of contexts ranging from security and the construction industry to particle physics and astronomy. However, emerging technologies and missions call for faster bolometers with lower noise. Here, we demonstrate a nanobolometer that exhibits roughly an order of magnitude lower noise equivalent power, $20\textrm{ zW}/\sqrt{\textrm{Hz}}$, than previously reported for any bolometer. Importantly, it is more than an order of magnitude faster than other low-noise bolometers, with a time constant of 30 $\mu$s at $60\textrm{ zW}/\sqrt{\textrm{Hz}}$. These results suggest a calorimetric energy resolution of $0.3\textrm{ zJ}=h\times 0.4$ THz with a time constant of 30 $\mu$s. Thus the introduced nanobolometer is a promising candidate for future applications requiring extreme precision and speed such as those in astronomy and terahertz photon counting.

Tiivistelmä Tässä etnografisessa tutkimuksessa havainnoitiin ja haastateltiin kahta peruskoulun fysiikan ja kemian opettajaa, joiden opetuksen korkea taso oli näkynyt sekä oppimistuloksissa että oppilaiden myönteisissä asenteissa fysiikan ja kemian opiskelua kohtaan. Molemmat opettajat olivat löytäneet vahvuuksiensa mukaisen lähestymistavan opetukseen. Toinen opettaja tuki aktiivisesti oppilaan itsenäistä työskentelyä kun taas toisen opettajan tunnit olivat strukturoidumpia. Hänellä oli taito selittää asiat selkeästi ja mielenkiintoisesti. Tutkimuksen opettajat ohjasivat kokeellista työskentelyä eri tavoin tekemällä siitä oppilaalle merkityksellisen. Havainnoinnin perusteella opettajan puheen tehtävänä on käsitteiden muodostamisen tukeminen luomalla merkityksellisiä yhteyksiä, oppilaan ymmärryksen tarkistaminen, sekä vuorovaikutuksen rakentaminen. Näistä tehtävistä keskeisin oli vuorovaikutuksen rakentaminen, mikä näkyi keskustelunomaisena puheena oppitunneilla.

In this contribution, a focal plane array (FPA) at submillimeter wavelengths is presented for security applications. The detectors are based on kinetic inductance bolometers. Two frequency selective absorber (FSA) sets were designed to implement a security imager. The effective pattern of the imager coupled to a black body point source over a wide frequency band (1:6) was demonstrated experimentally with excellent agreement to the one estimated by using a Fourier optics based technique.

Tiivistelmä Etnografisessa tutkimuksessa tarkastelimme kahden esimerkillisen fysiikan ja kemian opettajan käytänteitä ja erityisesti selittävän puheen roolia heidän opetuksessaan. Molempien opettajien opetuksen korkea taso oli näkynyt sekä oppimistuloksissa että oppilaiden myönteisissä asenteissa fysiikan ja kemian opiskelua kohtaan. Molemmat opettajat olivat löytäneet vahvuuksiensa mukaisen lähestymistavan opetukseen. Toisen opettajan tunnit olivat strukturoidumpia. Tällä opettajalla oli taito selittää asiat selvästi ja mielenkiintoisesti. Toinen opettaja puolestaan antoi oppilaille enemmän valinnanvapautta sekä tuki aktiivisesti itsenäistä työskentelyä. Perusopetuksen opetussuunnitelman perusteiden mukaan oppilaan tulisi osata kuvata ja selittää ilmiöitä fysiikan ja kemian keskeisten käsitteiden avulla. Seurattujen opettajien antamat selittämisen mallit tukivat oppilaiden kykyä keskustella käsitteistä sekä kertoa missä ilmiöt havaitaan, mitä käsitteitä niihin liittyy ja mitä sovelluksia niillä on. Tutkimuksen opettajat vaikuttivatkin oppilaan oppimiseen ja motivaatioon hyvällä selittämistaidollaan. Selittämällä opettajat nostivat esille esimerkiksi kokeellisen tutkimuksen vaiheita sekä laittoivat oppilaat huomaamaan käsitteen muodostuksen kannalta oleelliset asiat. Selittäminen sisälsi käsitteiden sitomisen koululaisten omaan maailmaan ja myös yhteiskuntaan. Oppilaat saivat myös käsityksen tiedon rakenteesta ja riippuvuussuhteista. Tämä edellytti toimivaa vuorovaikutusta, hyvää opettaja–oppilas-suhdetta. Yksi oleellisimmista huomioista oli se, että molemmat opettajat rakensivat opetustyylinsä persoonallisten ominaisuuksiensa mukaan. Selittämisen merkitys näkyi pitemmällä aikavälillä myös oppilaskeskeisessä opetuksessa, jossa opettaja pääasiassa ohjaa oppilaita itsenäiseen toimintaan. Oppituntien kokonaisvaltainen havainnointi vahvistaa tutkimuksia opettajan oikea-aikaisen ohjaavan roolin merkityksestä oppimiselle kokeellisessa työskentelyssä. Kun opettajat ohjaavat oppimista sensitiivisessä vuorovaikutuksessa oppilaisiin, he luovat hyviä suhteita oppilaisiin ja edesauttavat oppimista sekä antavat myös esimerkkejä selittämisestä. Tämä edellyttää tuntiaktiviteettien lisäksi oppitunnin vuorovaikutuksen suunnittelua tavoitteiden pohjalta. Abstract This ethnographical study focused on the practices of two highly effective Finnish comprehensive school science teachers, and especially on the role of teachers’ explanations during classroom interactions. The way teachers explained science and inquiry offered the students a model for explanations. Both teachers focused on explaining ideas and concepts as well guided students on making observations and inferences during inquiry tasks. Through this guidance, teachers supported the development of conceptual understanding about scientific models and theories, as well as understanding about the process of scientific inquiry and the interplay of science, technology and society. Both observed teachers had found an approach, which suited their strengths very well. The other used a method, in which students were more involved in providing the explanations, while the paid a closer attention to the way she explained and clarified ideas and concepts. The approaches of both teachers were based on the mutual respect and trust between the teacher and her students. It enabled the teachers to recognize the educational needs of the students and provide the right guidance at the right time. According to the observations of classroom practice as well as the teachers’ interviews, this mutual respect and trust was perhaps the most crucial factor supporting student engagement and learning.

A challenge for scaling up quantum processors using frequency-crowded, weakly anharmonic qubits is to drive individual qubits without causing leakage into non-computational levels of the others, while also minimizing the number of control lines. To address this, we implement single-qubit Wah-Wah control in a circuit QED processor with a single feedline for all transmon qubits, operating at the maximum gate speed achievable given the frequency crowding. Randomized benchmarking and quantum process tomography confirm alternating qubit control with $\leq$1% average error per computational step and decoherence-limited idling of one qubit while driving another with a Wah-Wah pulse train., Comment: 5 pages, 4 figures; supplemental material with 5 figures; improved figure quality

We report on fast tunability of an electromagnetic environment coupled to a superconducting coplanar waveguide resonator. Namely, we utilize a recently-developed quantum-circuit refrigerator (QCR) to experimentally demonstrate a dynamic tunability in the total damping rate of the resonator up to almost two orders of magnitude. Based on the theory it corresponds to a change in the internal damping rate by nearly four orders of magnitude. The control of the QCR is fully electrical, with the shortest implemented operation times in the range of 10 ns. This experiment constitutes a fast active reset of a superconducting quantum circuit. In the future, a similar scheme can potentially be used to initialize superconducting quantum bits., Comment: 4 pages, 2 figures

It is widely acknowledged today that an Inquiry-Based approach to Research and Innovation processes can improve the interest of students in studying scientific topics. Such approaches can enable students to have the opportunity to interact with cutting edge topics, research results and work with researchers and other societal actors to better align research processes and their outcomes with the values, needs and expectations of today's society. However, there is still no clear consensus between researchers about the impact that inquiry-based approaches have on the student scientific knowledge and conceptual understanding at different ages and cultural levels. This paper discusses these aspects from a vertical and interdisciplinary curriculum perspective. Firstly, the impact of a series of inquiry-based learning activities on the acquisition of scientific knowledge and in the development of pupils' positive attitudes toward science in pupils aged 10–13 is discussed. Secondly, a discussion on important preconditions needed for an introduction of cutting-edge topics to the classroom, and the role of the inquiry that has to be offered to students to effectively construct knowledge is considered at the pre-university level. Following this, an approach adopted by three large scale European projects (ESTABLISH, SAILS and OSOS) that focus on enhancing science education curricula, pedagogy and assessment practices and supporting science educators in embedding Inquiry-Based Education or Responsible Research and Innovation principles in science education is presented. Finally, an innovative Doctoral Degree in Sustainability Science, which seeks transformative education that challenges the attitudes of both professors and students is presented and some of its most relevant aspects are discussed.

Strand 14 of ESERA addresses an internationally increasingly recognized complex field of science education research: in-service teacher education and continued professional development of science teachers. It is obvious that the value and success of any educational system strongly corresponds with the quality of its teachers’ competences and practices. In this sense, it is not surprising that the strand on in-service science teacher education is always one of the most active strands of ESERA. Compared to the last ESERA conference proceedings, the number of papers presented in this strand was growing from 10 to 32 pieces.