Non-local multi-particle geometric phases in electronic intensity interferometry
4.07.2017
Date | 4.07.2017 |
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Time | 10:00 |
Place |
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Speaker | Sourin Das |
Area of expertise | Physics |
Host | Dep. Physik |
Contact | Zilberberg |
Abstract | Abs: Berry's discovery of the geometric phase in 1984 led to a deeper understanding of wide range of phenomena in different areas of physics starting from molecular physics to condensed matter systems. In this talk, I will first provide an introduction to the concept of geometric phase in spirit of Berry's definition and then relate it to its generalized version as anticipated in earlier works of Pancharatnam. I shall then apply Pancharatnam's ideas to obtain non-local and multi-particle geometric phase in the context of electronic version of the Hanbury-Brown and Twiss intensity interferometer. I will discuss a possible experimental realization of this effect by exploiting edge states of two-dimensional topological insulators (2d TI edge states). It will be shown that the electrical transport in quantum spin Hall (an example of the 2d TI state) edge can host a two particle Aharonov - Bohm (AB) effect in spin space which essentially is an example of multi-particle and non-local geometric phase. This two particle “spin A-B effect” stems from an effective AB flux piercing a two particle loop identified on the Bloch sphere which can be attributed to an abstract monopole of strength 1/2 placed at the origin of the sphere. |