visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
날짜 2020-09-24 09:00 
연사  
장소 Zoom Video 

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)

 

https://kaist.zoom.us/j/6108068959?pwd=TXV2OGlWdVRtcGhmNXVTRWlla2pHQT09


Meeting ID: 610 806 8959
 

Passcode: 131015

 

Topic: Searching for Dark Matter with a Superconducting Qubit

Abstract:

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)

https://webinar.kafe.or.kr

Seminar Name: Cryogenic Microwave Circuit Development at the NSTU

Password: None

 

Topic: Cryogenic Microwave Circuit Development at the NSTU

Abstract:

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 날짜 연사 제목
공지 2025-02-24 16:00    2025년 봄학기 콜로키움 안내
공지 2025-02-27 16:00    2025년 봄 물리학과 특별세미나 (광학/응집물리 분야)
285 2023-06-22 16:00    [High Energy Physics Seminar] The Branes Behind Generalized Symmetry Operators
284 2019-01-23 16:00    Ultrasensitive Microwave Bolometer: Opportunity for Axion Detectors file
283 2022-04-13 10:30    Harnessing topology and correlations from singularities in 3d-kagome metals
282 2024-05-08 16:30    [High Energy Theory Seminar] Black Holes from Heavy Operators in N=4 SYM
281 2023-08-23 16:00    [High Energy Theory Seminar] A spacetime tensor network for AdS3/CFT2
280 2023-01-09 16:00    Non-Hermitian Hopf-bundle Matter. Moon Jip Park (IBS-PCS)
279 2025-05-13 16:00  Mr. Heonjoon Park(Univ. Washington, USA)  Fractional Quantum Anomalous Hall Effect file
278 2020-12-11 14:30    Antisymmetric interlayer exchange coupling in magnetic multilayers
277 2024-01-24 15:00    Determination of single molecule loading rate during mechanotransduction file
276 2020-11-26 16:00    2020 가을학기 광학분야 특별세미나(Light Engineering Beyond the Diffraction Limit)
275 2024-04-11 16:00    Theoretical Studies of the Electric Field Induced Thermal Hall Effect in the Quantum Dimer Magnets XCuCl3 (X = Tl, K)
274 2016-10-17 11:00    IMS and examples of the studies on optoelectronic materials
273 2019-08-19 10:00    Tutorials on Multimode Quantum Optics in the Continuous Variable Regime file
272 2022-09-21 10:30    [Update 세미나 영상] Distinguished Lecture 'The Magic of Moiré Quantum Matter' Prof. Pablo Jarillo-Herrero(Department of Physics, MIT) file
271 2022-08-08 14:00    Classical Shadow Tomography for Analog Quantum Simulators
270 2025-04-21 16:00  Prof. Ambrose Sungseok Seo (Univ of Kentucky)  Condensed matter physics? All you gotta do is just meet me at the ... file
269 2020-12-09 10:00    Searching for the QCD axion with the ARIADNE experiment file
268 2019-08-22 16:00    Physics and Applications in Nanoelectronics and Nonomechanics file
267 2024-05-28 11:00    동적평균장 이론 소개
266 2022-03-25 11:00    (응집물리 세미나) Hund's metallicity in ruthenate systems file