Measurement of geometric phase for mixed states using single photon interferometry.
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.
Ericsson
Marie
M
Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
Achilles
Daryl
D
Barreiro
Julio T
JT
Branning
David
D
Peters
Nicholas A
NA
Kwiat
Paul G
PG