<< October 2019 >>
 
 >>
 >>
 >>
 >>
 >>
Sun Mon Tue Wed Thu Fri Sat
   1   2   3   4   5 
 6   7   8   9   10   11   12 
 13   14   15   16   17   18   19 
 20   21   22   23   24   25   26 
 27   28   29   30   31   
 
Add an Event Edit This Event

This Week at Physics

<< Spring 2019 Fall 2019 Spring 2020 >>
Subscribe to receive email announcements of events

Event Number 5154

  Thursday, October 31st, 2019

R. G. Herb Condensed Matter Seminar
Wrestling with ultrastrongly coupled parasitic modes in circuit quantum electrodynamics
Time: 11:00 am
Place: 5310 Chamberlin Hall
Speaker: Dr. Ivan Pechenezhskiy , University of Maryland
Abstract: Several promising superconducting qubit designs, including the protected ones, require superconductors operating as perfect inductors at microwave frequencies. As the value of the inductance increases with the inductor length, so does the parasitic capacitance due to the spatial extension of the inductor. Parasitic self-resonances formed this way impede the potential applications of extremely large inductances. Even in the simplest superconducting qubit circuit, in which a Josephson junction is shunted by a hyperinductor, the distributed nature of parasitic capacitance leads to an ultrastrong coupling of the parasitic modes to the qubit. This ultrastrong coupling of the parasitic modes prevents a perturbation theory treatment of the qubit excitation spectra. While a complete quantum description of the underlying qubit circuit is computationally prohibitive, diagonalization of an effective multi-mode Hamiltonian reproduces the experimental data both below and above the lowest parasitic modes. On the experimental side, the effects of the parasitic modes can be partially mitigated by releasing the qubit circuit off the substrate. This trick enables the realization of a new qubit design — blochnium.
Host: McDermott
Add this event to your calendar

©2013 Board of Regents of the University of Wisconsin System