BEGIN:VCALENDAR
VERSION:2.0
PRODID:icalendar-ruby
CALSCALE:GREGORIAN
METHOD:PUBLISH
BEGIN:VTIMEZONE
TZID:Europe/Vienna
BEGIN:DAYLIGHT
DTSTART:20230326T030000
TZOFFSETFROM:+0100
TZOFFSETTO:+0200
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=3
TZNAME:CEST
END:DAYLIGHT
BEGIN:STANDARD
DTSTART:20231029T020000
TZOFFSETFROM:+0200
TZOFFSETTO:+0100
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
TZNAME:CET
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DTSTAMP:20260424T143441Z
UID:6440f19fd5288876335492@ist.ac.at
DTSTART:20230622T100000
DTEND:20230622T110000
DESCRIPTION:Speaker: Roman Riwar\nhosted by Johannes Fink\nAbstract: Probab
 ly one of the most basic circuit elements is a linear capacitor\, which ac
 counts for the energy stored in the electric field built up when separatin
 g charges across different nodes of the device. The last years and decades
  have seen the emergence of a variety of more general capacitive elements\
 , with a nonlinear charge-voltage relationship\, for instance by means of 
 ferro-electric materials. In this talk\, I review some recent developments
  specific to quantum circuits. In the first part\, I revisit the physics o
 f quantum phase slip junctions\, which are currently regarded as nonlinear
  capacitors\, dual to the Josephson effect. I present a number of argument
 s why such junctions should actually be described as inductive elements in
 stead of capacitive ones. Our treatment allows for an unambiguous computat
 ion of thermodynamic quantities like the circuit's entropy or heat capacit
 ance\, and a slender integration of recent insights regarding time-depende
 nt flux driving. It further limits the valid forms of inductive couplings 
 to a generic electromagnetic environment\, and correctly predicts the size
  of the available computational space for qubit applications. In a second 
 part\, I show how quantum phase slips in regular transmons can nonetheless
  realize a genuine nonlinear capacitive element\, by partitioning the offs
 et charge induced by a nearby island. This element has a further noteworth
 y property: it is quasiperiodic in charge space\, and may thus be pivotal 
 to mimic transport versions of effects known from solid state physics\, su
 ch as Anderson localization or twistronics. Finally\, I provide a brief ou
 tlook on further recent ideas\, such as a topologically protected in-situ 
 control of the capacitance\, based on recently predicted Chern physics of 
 conventional Cooper-pair transistors.
LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101
 )\, ISTA
ORGANIZER:swiddman@ist.ac.at
SUMMARY:Roman Riwar: Old and new capacitances
URL:https://talks-calendar.ista.ac.at/events/4141
END:VEVENT
END:VCALENDAR