# Events

## Dudi Gershoni (Technion) Host: Ady

00:00

Drory auditorium

Weizmann Condensed Matter Physics Seminars

2020

12

February

## Ella Orion Lachman (Berkeley)

00:00

Drory auditorium

Weizmann Condensed Matter Physics Seminars

2020

05

February

## Non-Abelian geometric dephasing Speaker: Kyrylo Snizhko

13:15 - 14:15

Drory auditorium

Weizmann Condensed Matter Physics Seminars

Abstract...

Geometric phases are an important part of modern physics. Their applications range from explaining condensed matter effects to designing quantum computation protocols. At the same time, real systems are influenced by external environment (classical or quantum), which leads to dephasing. It turns out that apart from the conventional dynamic dephasing there exists a subleading extra term — geometric dephasing, which arises due to an interplay of the dynamic and geometric phases. Geometric dephasing can be expressed in terms of the Berry curvature and inherits a number of other properties from the geometric phase. While the effect has been known for some time in the context of Abelian geometric phases [1,2], its understanding for the non-Abelian case has been lacking until recently [3,4]. In this talk, I will introduce a framework allowing for a unified treatment of geometric dephasing — both Abelian and non-Abelian — in the language of gauge theories. I will explain the physical origin and implications of the effect, discuss a scheme for detecting the non-Abelian geometric dephasing using Majorana zero modes, and briefly mention where the effect may be important in condensed matter systems. References: [1] R. S. Whitney, Y. Makhlin, A. Shnirman, and Y. Gefen, Geometric Nature of the Environment-Induced Berry Phase and Geometric Dephasing, Phys. Rev. Lett. 94, 070407 (2005). [2] S. Berger, M. Pechal, P. Kurpiers, A. A. Abdumalikov, C. Eichler, J. A. Mlynek, A. Shnirman, Y. Gefen, A. Wallraff, and S. Filipp, Measurement of geometric dephasing using a superconducting qubit, Nat. Commun. 6, 8757 (2015). [3] K. Snizhko, R. Egger, and Y. Gefen, Non-Abelian Geometric Dephasing, Phys. Rev. Lett. 123, 060405 (2019), Editor's Suggestion. [4] K. Snizhko, R. Egger, and Y. Gefen, Non-Abelian Berry phase for open quantum systems: Topological protection versus geometric dephasing, Phys. Rev. B 100, 085303 (2019), Editor's Suggestion.

2020

22

January

## Elio Johannes Koenig-Tarasevich (Rutgers)

13:15 - 14:15

Drory auditorium

Weizmann Condensed Matter Physics Seminars

2020

19

January

## Andrey Chubukov (UMN)

13:15 - 14:15

Drory auditorium

Weizmann Condensed Matter Physics Seminars

2020

15

January

## Itamar Kimchi (UC Boulder)

13:15 - 14:15

Drory auditorium

Weizmann Condensed Matter Physics Seminars

2020

08

January

## Yoav Kalchheim (UCSB)

13:15 - 14:15

Drory auditorium

Weizmann Condensed Matter Physics Seminars

2020

01

January

## Anna Keselman

13:15 - 14:15

Drory auditorium

Weizmann Condensed Matter Physics Seminars

2019

22

December

There are currently no Internal Events to show.