Usually, most optical diodes with high nonreciprocal transmission ratio were accompanied with high insertion loss. The diode made of the asymmetry cavity filled with two-level atoms can simultaneously possess high nonreciprocal transmission ratio and low insertion loss, because the cavity can lower insertion loss and the bistability of the atom can enhance nonreciprocal transmission ratio. However, such diodes can only operate in a very narrow frequency band. In this article we explore two methods to achieve efficient diodes with a wide frequency range. One is using mixed atomic gas instead of a single atom and the other is replacing single-mode cavity with passive white light cavities. By using the two methods, a wide band optical diode with high nonreciprocal transmission ratio and low insertion loss is provided. It will be beneficial for improving the performance of broadband photonic chips and photonic communication.Usually, most optical diodes with high nonreciprocal transmission ratio were accompanied with high insertion loss. The diode made of the asymmetry cavity filled with two-level atoms can simultaneously possess high nonreciprocal transmission ratio and low insertion loss, because the cavity can lower insertion loss and the bistability of the atom can enhance nonreciprocal transmission ratio. However, such diodes can only operate in a very narrow frequency band. In this article we explore two methods to achieve efficient diodes with a wide frequency range. One is using mixed atomic gas instead of a single atom and the other is replacing single-mode cavity with passive white light cavities. By using the two methods, a wide band optical diode with high nonreciprocal transmission ratio and low insertion loss is provided. It will be beneficial for improving the performance of broadband photonic chips and photonic communication.

Optics ExpressSep 4, 20240 citations

An entangled-light-emitting diode

C. L. Salter, R. M. Stevenson, Ian A. Farrer +3 more

NatureJun 1, 2010354 citations

A spooky light-emitting diode

Val Zwiller

Nature PhotonicsJul 30, 20103 citations

Single-Photon Diode by Exploiting the Photon Polarization in a Waveguide

Yuecheng Shen, Matthew Bradford, Jung‐Tsung Shen

A single-photon optical diode operates on individual photons and allows unidirectional propagation of photons. By exploiting the unique polarization configuration in a waveguide, we show here that a single-photon optical diode can be accomplished by coupling a quantum impurity to a passive, linear optical waveguide which possesses a locally planar, circular polarization. We further show that the diode provides a near unitary contrast for an input pulse with finite frequency bandwidth and can be implemented in a variety of types of waveguides. Moreover, the performance of the diode is not sensitive to the intrinsic dissipation of the quantum impurity.A single-photon optical diode operates on individual photons and allows unidirectional propagation of photons. By exploiting the unique polarization configuration in a waveguide, we show here that a single-photon optical diode can be accomplished by coupling a quantum impurity to a passive, linear optical waveguide which possesses a locally planar, circular polarization. We further show that the diode provides a near unitary contrast for an input pulse with finite frequency bandwidth and can be implemented in a variety of types of waveguides. Moreover, the performance of the diode is not sensitive to the intrinsic dissipation of the quantum impurity.

Physical Review LettersOct 17, 2011110 citations

Impact of Surface Treatment on Noise in PL-Measurements of Silicon Vacancies in 4H-SiC Lateral pin-Diodes

Jannik H. Schwarberg, Fabian Magerl, Susanne Beuer +11 more

Silicon vacancies ( $V_\mathrm{Si}$ ) in 4H-SiC are promising candidates for quantum technologies due to their long spin coherence times and integrability into mature semiconductor platforms. However, conventional CMOS-compatible processing introduces significant photoluminescence noise from passivation layers and crystal damage, degrading color center coherence and excitation linewidths. This work evaluates strategies to minimize such background noise. Thermally grown oxides with nitrogen monoxide annealing provide excellent low-noise passivation, remaining stable during subsequent $600\,^{\circ}\mathrm{C}$ thermal treatments. Furthermore, combining reactive ion etching with atomic layer etching eliminates ion-induced surface damage. Into lateral pin-diodes, used for stark shift and photoluminescent excitation linewidth tuning, a selectively etched optical window is integrated. These devices show ideal electrical properties -- blocking up to $150\,\mathrm{V}$ with leakage current below $10\,\mathrm{pA}/μ\mathrm{m}$ -- while significantly enhancing the $V_\mathrm{Si}$ environment. Single emitters in these pin-diodes show an increased signal-to-noise ratio of 15 for near-surface and of 50 for deeper emitters on both c-plane and a-plane wafers.Silicon vacancies ($V_\mathrm{Si}$) in 4H-SiC are promising candidates for quantum technologies due to their long spin coherence times and integrability into mature semiconductor platforms. However, conventional CMOS-compatible processing introduces significant photoluminescence noise from passivation layers and crystal damage, degrading color center coherence and excitation linewidths. This work evaluates strategies to minimize such background noise. Thermally grown oxides with nitrogen monoxide annealing provide excellent low-noise passivation, remaining stable during subsequent $600\,^{\circ}\mathrm{C}$ thermal treatments. Furthermore, combining reactive ion etching with atomic layer etching eliminates ion-induced surface damage. Into lateral pin-diodes, used for stark shift and photoluminescent excitation linewidth tuning, a selectively etched optical window is integrated. These devices show ideal electrical properties -- blocking up to $150\,\mathrm{V}$ with leakage current below $10\,\mathrm{pA}/μ\mathrm{m}$ -- while significantly enhancing the $V_\mathrm{Si}$ environment. Single emitters in these pin-diodes show an increased signal-to-noise ratio of 15 for near-surface and of 50 for deeper emitters on both c-plane and a-plane wafers.

quant-pharXiv:2605.24157May 26, 2026

Opto-Optical Modulation

ScienceOct 27, 20050 citations

Silicon vacancies (

V_\mathrm{Si}

) in 4H-SiC are promising candidates for quantum technologies due to their long spin coherence times and integrability into mature semiconductor platforms. However, conventional CMOS-compatible processing introduces significant photoluminescence noise from passivation layers and crystal damage, degrading color center coherence and excitation linewidths. This work evaluates strategies to minimize such background noise. Thermally grown oxides with nitrogen monoxide annealing provide excellent low-noise passivation, remaining stable during subsequent

600\,^{\circ}\mathrm{C}

thermal treatments. Furthermore, combining reactive ion etching with atomic layer etching eliminates ion-induced surface damage. Into lateral pin-diodes, used for stark shift and photoluminescent excitation linewidth tuning, a selectively etched optical window is integrated. These devices show ideal electrical properties -- blocking up to

150\,\mathrm{V}

with leakage current below

10\,\mathrm{pA}/μ\mathrm{m}

-- while significantly enhancing the

V_\mathrm{Si}

environment. Single emitters in these pin-diodes show an increased signal-to-noise ratio of 15 for near-surface and of 50 for deeper emitters on both c-plane and a-plane wafers.