Measurement of geometric phase for mixed states using single photon interferometry.
نویسندگان
چکیده
Geometric phase may enable inherently fault-tolerant quantum computation. However, due to potential decoherence effects, it is important to understand how such phases arise for mixed input states. We report the first experiment to measure mixed-state geometric phases in optics, using a Mach-Zehnder interferometer, and polarization mixed states that are produced in two different ways: decohering pure states with birefringent elements; and producing a nonmaximally entangled state of two photons and tracing over one of them, a form of remote state preparation.
منابع مشابه
Off-diagonal Mixed State Phases in Unitary Evolution A
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عنوان ژورنال:
- Physical review letters
دوره 94 5 شماره
صفحات -
تاریخ انتشار 2005