• HOME
  • >
  • 소식
  • >
  • 세미나
장소 Zoom Video 
일시 Sep. 24(Thu), 09:00~, Sep. 24(Thu), 16:00 ~ 
연사 Akash V. Dixit (University of Chicago), Dr. Boris Ivanov (Novosibirsk State Technical University) 

Speaker: Akash V. Dixit (University of Chicago)


Date: September 24, 2020 (Thursday)


Time: 9:00 AM


Venue: Zoom Video Conference System (Please click the link below)

Meeting ID: 610 806 8959

Passcode: 131015


Topic: Searching for Dark Matter with a Superconducting Qubit


The gravitational evidence for the existence of dark matter is extensive 1 , yet thus far, dark matter has evaded direct detection in terrestrial experiments. Detection mechanisms for low mass dark matter candidates such as the axion 2–5 or hidden photon 6,7 leverage potential interactions with electromagnetic fields, whereby the dark matter (of unknown mass) on rare occasion converts into a single photon 8,7. Current dark matter searches operating at microwave frequencies, use a resonant cavity to coherently accumulate the field sourced by the dark matter and use a quantum limited linear amplifier to read out the cavity signal 9–12. Here, we report the development of a novel microwave photon counting technique and use it to set a new exclusion limit on hidden photon dark matter. We constrain the kinetic mixing angle to  ≤ 1.82 × 10−15 in a narrow band around 6.011 GHz (24.86 µeV) with an integration time of 8.33 s. We operate a superconducting qubit to make repeated quantum non-demolition measurements of cavity photons and apply a hidden Markov model analysis to reduce the noise to 15.7 dB below the quantum limit, with performance limited by the residual population of the system. The techniques presented here will dramatically improve the sensitivity of future dark matter searches in the range of 3-30 GHz and are generally applicable to measurements that require high sensitivity to inherently low signal photon rates.


Seminar Invitation (September 24, 2020), 4 PM

Speaker: Dr. Boris Ivanov (Novosibirsk State Technical University)

Date: September 24, 2020 (Thursday)

Time: 4:00 PM

Venue: Webinar Video Conference System (Please click the link below)

Seminar Name: Cryogenic Microwave Circuit Development at the NSTU

Password: None


Topic: Cryogenic Microwave Circuit Development at the NSTU


During the seminar I am going to show the last scientific results of 4 research performed in the Laboratory of Quantum and Cryogenic Electronics. I will concentrate the major part of the talk around cryogenic amplifiers design, development and characterization. Thus, the cryogenic low noise amplifier with the noise temperature of 6 K and gain value of more than 30 dB is shown for the frequency range from 6 to 12 GHz. Based on such microwave amplifiers the superconducting X-mon qubit structures were measured. The experiments with qubits were performed at continues microwave field and with short microwave pulses. The qubit energy spectrums were obtained and based on the AC-Stark experiment the low average photon number close to single photon mode in qubit-resonator structure was obtained. From the other side for the bolometer circuits readout and Josephson junctions measurements the low frequency cryogenic amplifiers were designed and characterized. The minimum voltage noise density corresponds to 150 pV/root(Hz) with the gain value of more than 60 dB for the presented amplifiers.

번호 일시 장소 연사 제목
303 Oct 23 (Fri.), 14:00 PM  E6-2 #1323  Prof. Ivan Savenko (University of Science and Technology & IBS PCS)  Plasmon spectroscopy of low-dimensional superconductors in fluctuating regime file
302 Oct. 16 (Fri.), 04:00 PM  Dr. Daesu Lee  Hidden room-temperature ferroelectricity in CaTiO3 revealed by a metastable octahedral rotation pattern file
301 Oct. 16 (Fri.), 02:30 PM  Dr. Chulki Kim  Nanoscale magnetic resonance detection towards nano MRI file
300 October 15, 2020 (Thursday  CAPP Seminar Room #C303, Creation Hall (3F), KAIST Munji Campus  Prof. Gil-Ho Lee (POSTECH)  Graphene-based Josephson junction microwave bolometer file
299 Oct. 15, 4pm  (  정현석 교수님 (SNU)  Towards resource-efficient and fault-tolerant quantum computation with nonclassical light
298 Oct 9 (Fri), 09:00 AM  Prof. Tim Hsieh (Perimeter Institute)  Quantum Many-Body Simulation file
297 October 15, 5:00pm  Dr. Samuli Autti  Time crystals, quasicrystals, and time crystal dynamics in the superfluid universe file
» Sep. 24(Thu), 09:00~, Sep. 24(Thu), 16:00 ~  Zoom Video  Akash V. Dixit (University of Chicago), Dr. Boris Ivanov (Novosibirsk State Technical University)  (CAPP/IBS)Searching for Dark Matter with a Superconducting Qubit , Cryogenic Microwave Circuit Development at the NSTU file
295 Sep.28. 5:30 pm  Zoom webinar  Burkard Hillebrands (TU Kaiserslautern, Germany)  KAIST Global Forum for Spin and Beyond(Fourth Forum) file
294 Sep. 22nd 9:30 AM  Zoom webinar  Prof. Xu Yi (Univ. of Virginia, USA)  Physics and applications of soliton microcombs(Quantum- & Nano-Photonics) file
293 Sep. 11(Fri), 14:00~  zoom  이관형교수/SNU, 이상윤교수/GIST  SRC Seminar file
292 Sep. 14(Mon) 17:30~  Zoom webinar  Teruo Ono (Kyoto U. Japan)  KAIST Global Forum for Spin and Beyond (Third Forum) file
291 Aug, 25(Tue), 20:00~  Zoom webinar  Mark D. Stiles (NIST, USA)  KAIST Global Forum for Spin and Beyond (Second Forum) file
290 Aug. 17(Mon), 20:00~  Zoom webinar  Mark D. Stiles (NIST, USA)  Using magnetic tunnel junctions to compute like the brain file
289 July 2, 2020 (Thursday)  Zoom Video Conference Seminar  Dr. Emmanuel Flurin (CEA Saclay)  An irreversible qubit-photon coupling for the detection of itinerant microwave photons file
288 February 20 (Thu), 4:00 PM  #1323, E6-2  Seunghyun Khim  Unconventional superconductivity in the locally non-centrosymmetric heavy-fermion CeRh2As2 file
287 February 13th (Thur.), 16:30 PM  E6-6, #119  Dr. Seyoon Kim(University of Wisconsin-Madison)  Enhanced Light-Matter Interactions in Graphene with Noble Metal Plasmonic Structures file
286 February 12(Web.)  E6-2, #5318  Prof. Kunio Kaneta  From inflation to new weak-scale file
285 January 17 (Fri), 4:00 PM  #1323, E6-2  Hiroki Ikegami  Symmetry Breaking and Topology in Superfluid 3He file
284 Dec 27 (Fri), 3:00 PM  #5318, E6-2  Han Gyeol Suh  The superconducting order parameter puzzle of Sr2RuO4 file