title: Highly stable polarization independent Mach-Zehnder interferometer.
abstract: We experimentally demonstrate optical Mach-Zehnder interferometer utilizing displaced Sagnac configuration to enhance its phase stability. The interferometer with footprint of 27×40 cm offers individually accessible paths and shows phase deviation less than 0.4° during a 250 s long measurement. The phase drift, evaluated by means of Allan deviation, stays below 3° or 7 nm for 1.5 h without any active stabilization. The polarization insensitive design is verified by measuring interference visibility as a function of input polarization. For both interferometer's output ports and all tested polarization states the visibility stays above 93%. The discrepancy in visibility for horizontal and vertical polarization about 3.5% is caused mainly by undesired polarization dependence of splitting ratio of the beam splitter used. The presented interferometer device is suitable for quantum-information and other sensitive applications where active stabilization is complicated and common-mode interferometer is not an option as both the interferometer arms have to be accessible individually.
authors.affiliation: Department of Optics, Faculty of Science, Palacký University, 17. listopadu 1192/12, 77146 Olomouc, Czech Republic.
authors.forename: Michal
authors.initials: M
authors.lastname: Mičuda
authors.affiliation: Department of Optics, Faculty of Science, Palacký University, 17. listopadu 1192/12, 77146 Olomouc, Czech Republic.
authors.forename: Ester
authors.initials: E
authors.lastname: Doláková
authors.affiliation: Department of Optics, Faculty of Science, Palacký University, 17. listopadu 1192/12, 77146 Olomouc, Czech Republic.
authors.forename: Ivo
authors.initials: I
authors.lastname: Straka
authors.affiliation: Department of Optics, Faculty of Science, Palacký University, 17. listopadu 1192/12, 77146 Olomouc, Czech Republic.
authors.forename: Martina
authors.initials: M
authors.lastname: Miková
authors.affiliation: Department of Optics, Faculty of Science, Palacký University, 17. listopadu 1192/12, 77146 Olomouc, Czech Republic.
authors.forename: Miloslav
authors.initials: M
authors.lastname: Dušek
authors.affiliation: Department of Optics, Faculty of Science, Palacký University, 17. listopadu 1192/12, 77146 Olomouc, Czech Republic.
authors.forename: Jaromír
authors.initials: J
authors.lastname: Fiurášek
authors.affiliation: Department of Optics, Faculty of Science, Palacký University, 17. listopadu 1192/12, 77146 Olomouc, Czech Republic.
authors.forename: Miroslav
authors.initials: M
authors.lastname: Ježek