Nonclassical Light from Semiconductor Lasers and LEDs

ISBN-13: 9783642632082 / Angielski / Miękka / 2012 / 244 str.

Jungsang Kim; Seema Somani; Yoshihisa Yamamoto

Opis

The quantum statistical properties of light generated in a semiconductor laser and a light-emitting diode (LED) have been a ?eld of intense research for more than a decade. This research monograph discusses recent research activities in nonclassical light generation based on semiconductor devices, performed mostly at Stanford University. When a semiconductor material is used as the active medium to generate photons, as in semiconductor lasers and LEDs, the ?ow of carriers (electrons andholes)isconvertedintoa?owofphotons. Providedthattheconversionis fast and e?cient, the statistical properties of the carriers ("pump noise") can be transferred to the photons; if pump noise can be suppressed to below the shot noise value, the noise in the photon output can also be suppressed below thePoissonlimit. Sinceelectronsandholesarefermionsandhavecharges, the statisticalpropertiesoftheseparticlescanbesigni?cantlydi?erentfromthose of photons if the structure of the light-emitting device is properly designed to provide interaction between these particles. There has been a discrepancy between the theoretical understanding and experimental observation of noise in a macroscopic resistor until very - cently. The dissipation that electrons experience in a resistor is expected to accompany the ?uctuation due to partition noise, leading to shot noise in the large dissipation limit as is the case with photons. Experimental observation shows that thermal noise, expected only in a thermal-equilibrium situation (zero-bias condition), is the only source of noise featured by a resistor, - dependent of the current.

Spis treści

1. Nonclassical Light.- 1.1 Classical Description of Light.- 1.2 Quantum Description of Light.- 1.3 Coherent State, Squeezed State and Number-Phase Squeezed State.- 1.4 Quantum Theory of Photodetection and Sub-Poisson Photon Distribution.- 1.5 Quantum Theory of Second-Order Coherence and Photon Antibunching.- 1.6 Quantum Theory of Photocurrent Fluctuation and Squeezing.- 2. Noise of p-n Junction Light Emitters.- 2.1 Introduction.- 2.2 Junction Voltage Dynamics: the Poisson Equation.- 2.3 Semiclassical Langevin Equation for Junction Voltage Dynamics.- 2.3.1 Mesoscopic Case (r ? 1).- 2.3.2 Macroscopic Case (r ? 1).- 2.4 Noise Analysis of an LED.- 2.4.1 Steady-State Conditions.- 2.4.2 Linearization.- 2.4.3 Photon-Number Noise.- 2.4.4 Noise in the External Circuit Current.- 2.4.5 Correlation Between Carrier Number and Junction Voltage.- 2.4.6 Correlation Between Photon Flux and Junction Voltage.- 2.5 Summary.- 3. Sub-Poissonian Light Generation in Light-Emitting Diodes.- 3.1 Introduction.- 3.2 Physical Mechanism of Pump-Noise Suppression.- 3.3 Measurement of the Squeezing Bandwidth.- 3.4 Summary.- 4. Amplitude-Squeezed Light Generation in Semiconductor Lasers.- 4.1 Introduction.- 4.2 Interferometric Measurement of Longitudinal-Mode-Partition Noise.- 4.2.1 Principle.- 4.2.2 Experimental Setup.- 4.3 Grating-Feedback External-Cavity Semiconductor Laser.- 4.3.1 Experimental Setup and Procedure.- 4.3.2 Experimental Results.- 4.3.3 Discussion.- 4.4 Injection-Locked Semiconductor Laser.- 4.4.1 Experimental Setup and Procedure.- 4.4.2 Experimental Results.- 4.4.3 Discussion.- 4.4.4 Modeling of the Noise of an Injection-Locked Laser.- 4.5 Summary.- 5. Excess Intensity Noise of a Semiconductor Laser with Nonlinear Gain and Loss.- 5.1 Introduction.- 5.2 Physical Models for Nonlinearity.- 5.2.1 Nonlinear Gain.- 5.2.2 Nonlinear Loss.- 5.3 Noise Analysis Using Langevin Rate Equations.- 5.4 Numerical Results.- 5.4.1 Numerical Parameters.- 5.4.2 Results.- 5.5 Discussion: Effect of Saturable Loss.- 5.6 Comparison of Two Laser Structures with Respect to Saturable Loss.- 5.6.1 Estimate of the Loss by Si DX Centers.- 5.6.2 Experimental Verification of the Saturable Loss.- 5.6.3 Explanation for the Excess Noise in QW Lasers.- 5.7 Summary.- 6. Transverse-Junction-Stripe Lasers for Squeezed Light Generation.- 6.1 Introduction.- 6.2 Fabrication.- 6.2.1 Si Diffusion and Intermixing.- 6.2.2 High V/III Ratio for Sharper Interfaces.- 6.2.3 P Doping by Zn Diffusion.- 6.2.4 Devices.- 6.3 DC Characterization: Threshold, Loss and Quantum Efficiency.- 6.4 Intensity Noise.- 6.4.1 Influence of High V/III Ratio.- 6.4.2 Optimization of External Coupling Efficiency.- 6.4.3 Polarization-Partition Noise.- 6.4.4 Longitudinal-Mode-Partition Noise.- 6.4.5 Suppressed 1/f Noise.- 6.5 Summary.- 7. Sub-Shot-Noise FM Spectroscopy.- 7.1 Introduction.- 7.2 Advantages of Semiconductor Lasers.- 7.3 Signal-to-Noise Ratio (SNR).- 7.4 Realization of Sub-Shot-Noise FM Spectroscopy.- 7.4.1 Frequency and Noise Control by Injection Locking.- 7.4.2 Effect of Injection Locking on Intensity Noise.- 7.4.3 Suppression of Residual AM by Injection-Locking.- 7.4.4 Suppression of Residual AM by Dual Pump Current Modulation.- 7.4.5 Expected Lineshape.- 7.4.6 Spectroscopic Setup.- 7.5 Experimental Results.- 7.6 Future Prospects.- 8. Sub-Shot-Noise FM Noise Spectroscopy.- 8.1 Introduction.- 8.2 Principle of FM Noise Spectroscopy.- 8.3 Signal-to-Noise Ratio and the Advantage of Amplitude Squeezing.- 8.4 Sub-Shot-Noise Spectroscopy.- 8.4.1 Experimental Setup.- 8.4.2 Laser Trapping and Cooling of Rb.- 8.4.3 Expected Optical Transitions in a Magneto-Optic Trap.- 8.4.4 Sample Probing.- 8.4.5 Experimental Result.- 8.5 Phase-Sensitive FM Noise Spectroscopy.- 8.5.1 Experimental Setup.- 8.5.2 Experimental Results.- 8.6 Summary.- 9. Sub-Shot-Noise Interferometry.- 9.1 Introduction.- 9.2 Sensitivity Limit of an Optical Interferometer.- 9.3 Amplitude-Squeezed Light Injection in a Dual-Input Mach-Zehnder Interferometer.- 9.4 Sub-Shot-Noise Phase Measurement.- 9.4.1 Experimental Procedure.- 9.4.2 Experimental Result.- 9.5 Dual-Input Michelson Interferometer.- 9.5.1 Operation Principle.- 9.5.2 Sensitivity of a Dual-Input Michelson Interferometer.- 9.5.3 Sub-Shot-Noise Interferometry.- 9.6 Summary and Future Prospects.- 10. Coulomb Blockade Effect in Mesoscopic p-n Junctions.- 10.1 Introduction.- 10.2 Calculation of Resonant Tunneling Rates.- 10.2.1 Transmittance of the Barrier.- 10.2.2 Tunneling Matrix Element.- 10.2.3 Electron Tunneling Current Density into the Central QW.- 10.2.4 Effect of Inhomogeneous Broadening.- 10.3 Coulomb Blockade Effect on Resonant Tunneling.- 10.4 Coulomb Staircase.- 10.4.1 DC Voltage Bias Condition.- 10.4.2 DC + AC Voltage Bias Condition.- 10.5 Turnstile Operation.- 10.6 Monte-Carlo Simulations.- 10.7 Summary.- 11. Single-Photon Generation in a Single-Photon Turnstile Device.- 11.1 Introduction.- 11.2 Device Fabrication.- 11.2.1 Wafer Design and Growth.- 11.2.2 Ohmic Contact Formation.- 11.2.3 Device Definition: Electron-Beam Lithography.- 11.2.4 Metal Evaporation and Liftoff.- 11.2.5 Device Isolation: ECR-RIE.- 11.2.6 Surface Passivation.- 11.2.7 Planarization and Top-Contact Evaporation.- 11.3 Observation of the Coulomb Staircase.- 11.4 Single-Photon Turnstile Device.- 11.4.1 Preliminary Characterization.- 11.4.2 Experimental Setup.- 11.4.3 Electrical Characterization.- 11.4.4 Optical Characterization.- 11.5 Summary.- 12. Single-Photon Detection with Visible-Light Photon Counter.- 12.1 Introduction.- 12.2 Comparison of Single-Photon Detectors.- 12.2.1 Photomultiplier Tubes (PMTs).- 12.2.2 Avalanche Photodiodes (APDs).- 12.2.3 Superconducting Tunnel Junctions (STJs).- 12.2.4 Solid-State Photomultipliers (SSPMs) and Visible-Light Photon Counters (VLPCs).- 12.3 Operation Principle of a VLPC.- 12.4 Single-Photon Detection System Based on a VLPC.- 12.5 Quantum Efficiency of a VLPC.- 12.6 Theory of Noise in Avalanche Multiplication.- 12.6.1 Excess Noise Factor (ENF).- 12.6.2 Noise Power Spectral Density of the Multiplied Photocurrent.- 12.6.3 Effect of ENF in the Pulse-Height Distribution.- 12.7 Excess Noise Factor of a VLPC.- 12.7.1 Digital Measurement of the Pulse-Height Distribution.- 12.7.2 Analog Noise Power Spectral Density Measurement.- 12.8 Two-Photon Detection with a VLPC.- 12.8.1 Twin Photon Generation in Optical Parametric Downconversion.- 12.8.1 Characterization of Two-Photon Detection with VLPC.- 12.9 Summary.- 13. Future Prospects.- 13.1 Introduction.- 13.2 Regulated and Entangled Photons from a Single Quantum Dot.- 13.3 Single-Mode Spontaneous Emission from a Single Quantum Dot in a Three-Dimensional Microcavity.- 13.4 Lasing and Squeezing of Exciton-Polaritons in a Semiconductor Microcavity.- A. Appendix: Noise and Correlation Spectra for Light-Emitting Diode.- A.1 Linearization.- A.2 LED Photon Noise Spectral Density.- A.3 External Current Noise Spectral Density.- A.4 Junction-Voltage-Carrier-Number Correlation.- A.5 Photon-Flux -Junction-Voltage Correlation.- References.

Blurb

The quantum statistical properties of the light wave generated in a semiconductor laser or a light-emitting diode (LED) has been a field of intense research for more than a decade. This research monograph discusses recent research activities in nonclassical light generation based on semiconductor devices. This volume is composed of four major parts. The first discusses the generation of sub-shot-noise light in macroscopic pn junction light-emitting devices, including semiconductor laser and light-emitting diodes. The second part discusses the application of squeezed light in high-precision measurement, including spectroscopy and interferometry. The third part addresses the Coulomb blockade effect in a mesoscopic pn junction and the generation of single photon states. The last part covers the detection of single photons using a visible light photon counter.