a 2 www.rle.mit.edu/qoptics 1 Single-Mode Quantized - - PDF document

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Optical and Quantum Communications Group www.rle.mit.edu/qoptics October 6, 2016

6.453 Quantum Optical Communication Lecture 9 Jeffrey H. Shapiro

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6.453 Quantum Optical Communication — Lecture 9 § Announcements

§ Turn in problem set 4 § Pick up problem set 4 solution, problem set 5, lecture notes, slides

§ Single-Mode Photodetection

§ Direct Detection — reprise § Homodyne Detection — reprise § Heterodyne Detection — semiclassical versus quantum § Realizing the measurement

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Single-Mode Quantized Electromagnetic Field § Photon-Units Field Operator on Constant-z Plane:

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§ Photon Annihilation and Creation Operators:

with canonical commutation relation

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Direct Detection: Semiclassical versus Quantum § Single-Mode Photon Counter: Semiclassical Description § Single-Mode Photon Counter: Quantum Description

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Single-Mode Balanced Homodyne Receiver § Semiclassical Description: § Quantum Description:

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Homodyne Detection: Semiclassical Theory § Signal and Local Oscillator Fields: § Strong Local-Oscillator Condition: § Characteristic Function Derivation:

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Homodyne Detection: Quantum Theory § Signal and Local Oscillator Field Operators: § Local-Oscillator State: § Measurement Operator:

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Single-Mode Balanced Heterodyne Receiver § Semiclassical Description: § Quantum Description:

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Heterodyne Detection: Semiclassical Theory § Signal and Local Oscillator Fields: § Strong Local-Oscillator Condition: § Characteristic Function Derivation: random process theory

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Heterodyne Detection: Quantum Theory § Signal and Local Oscillator Field Operators: § Local-Oscillator State: § Simultaneous Measurement of Commuting Observables:

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Coming Attractions: Lecture 10 § Lecture 10: Single-Mode Photodetection

§ Signatures of non-classical light § Squeezed-state waveguide tap

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6.453 Quantum Optical Communication

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