visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
날짜 2020-09-24 09:00 
일시 Sep. 24(Thu), 09:00~, Sep. 24(Thu), 16:00 ~ 
장소 Zoom Video 
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)

 

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 장소 제목
414 2022-03-29 10:00  E6 #1501/zoom, E6 #2502/zoom  Non-reciprocal phase transitions file
413 2022-10-04 16:00  E6 #2501  Distinguishing 6d (1, 0) SCFTs
412 2024-08-16 11:00  E6 1322 (no zoom broadcasting)  Cathodoluminescence for nanophotonics: Applications to plasmonic bandgap materials and perovskite semiconductors file
411 2022-05-10 16:00  E6 1323  (광학분야 특별세미나)Testing quantum thermodynamics using quantum optics
410 2022-04-28 16:00  E6 1323  (광학분야 특별세미나)Adiabaticity and symmetry in optical waveguide design
409 2022-05-26 16:00  E6 1323  (광학분야 특별세미나)Topological photonic devices
408 2022-04-14 16:00  E6 1323  (광학분야 특별세미나)Holographic tomography of dielectric tensors at optical frequency
407 2023-02-28 11:00  E6 Room(#1322)  Topotactic redox engineering toward novel material file
406 2022-06-23 11:00  E6 Room(#1322)  JILA’s search for the electron’s Electric Dipole Moment (eEDM) to probe physics beyond the standard model file
405 2018-11-22 15:00  E6 Room(#1323)  Experimental and Computational Study on Physical Properties based on Granular System file
404 2019-08-06 16:00  E6 Room(#1323)  Visualization of in-plane piezoresponse vector fields file
403 2019-08-16 14:00  E6 Room(#1323)  Multiferroic and Magnetoelectric Effects by Tailoring Interfacial Chemistry and Physics in Correlated Oxides file
402 2019-05-08 16:00  E6 Room(#1323)  Imaging valley dependent electron transport in 2D semiconductors file
401 2019-08-01 14:00  E6 Room(#1323)  Low-density Superconductivity in SrTiO3 Probed by Planar Tunneling Spectroscopy file
400 2022-05-25 14:00  E6 Room(#2501)  Atomic-level insights into ferroelectric switching and preferred orientation of ultrathin hafnia file
399 2019-07-08 14:00  E6, #1322  Ultrabroadband squeezed pulses and their relation to relativity file
398 2024-02-16 10:00  E6, #1323  Optical conductivity of superconducting states driven by Van Hove singularities
397 2023-07-10 16:00  E6, #1323  Electronic structures of magnetic and non-magnetic ordering in d- and f-electrons systems
396 2022-05-02 16:00  E6, #1501  What can we learn from the history of science and technology?(우리말강의)
395 2022-03-21 16:00  E6, #1501  Multi-wavelength Studies on Relativistic Jets from Gamma-ray Bright Active Galactic Nuclei