Telefilters, telemirrors, and causality

Abstract

We present new theoretical models for quantum optical mode-selective filters and mirrors using continuous-variable teleportation. We call these devices telefilters and telemirrors respectively. Both devices act as the identity channel on a mode of interest from an input multi-mode field while filtering or reflecting all the orthogonal modes. We utilise these models to analyse a causality problem in relativistic quantum optics, specifically the apparently acausal transmission and propagation of temporally delocalised wavepackets through mode-selective mirrors. Firstly, we show how telemirrors - and thus mode-selective operations generally - enact a fundamental time-delay on such wavepackets, which is necessary in order to prevent violations of causality. In an attempt to circumvent this delay, we next consider teleporting the independent temporal components of the input field separately and continuously, that is, performing operations on-the-run. In this scenario, the telemirror transmits the mode of interest as well as orthogonal modes which carry with them uncorrelated noise. In this scenario, the device may be considered mode-discriminating but not mode-selective.

14+12 pages, 11 figures

References in corpus (11)

• Detection of 15 dB Squeezed States of Light and their Application for the Absolute Calibration of Photoelectric Quantum Efficiency
• A Quantum Pulse Gate based on Spectrally Engineered Sum Frequency Generation
• From quantum pulse gate to quantum pulse shaper -- enigneered frequency conversion in nonlinear optical waveguides
• Spectral structure and decompositions of optical states, and their applications
• Experimental generation of multi-photon Fock states
• Quantum Teleportation with Continuous Variables: a survey
• Effects of time ordering in quantum nonlinear optics
• Spectral density matrix of a single photon measured
• Multipartite Causal Correlations: Polytopes and Inequalities
• Relativistic causality in particle detector models: Faster-than-light signalling and "Impossible measurements"
• Universal Transformation of Displacement Operators and its Application to Homodyne Tomography In Differing Relativistic Reference Frames