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Optics and Photonics News

A Photon with No Area

Marco Bellini, Luca Costanzo, Daniele Pellegrino, Alessandro Zavatta, Antônio José Marques Nogueira Coêlho, Milrian S. Mendes, K. N. Cassemiro, L. H. Acioli, D. Felinto

Published Dec 1, 2016• 0 citations
OpenAlex

Abstract

Single photons are ideal information carriers, but their limited interaction among themselves and with the surrounding environment poses a major challenge for developing a completely optical quantum processor. One possible solution lies in hybrid photon-atom approaches, but common sense suggests that an efficient coupling can be achieved only with correspondingly narrowband resonant single photons, and that ultrashort single photons with bandwidths in the THz range would be useless for this purpose given their very weak interaction with atoms. In recent experiments, we have shown that, against common intuition, a single photon of extremely short duration, and thus possessing a wide range of different colors, can still strongly interact with very monochromatic atoms.

Related papers

Zero-Area Single-Photon Pulses

L. S. Costanzo, A. S. Coelho, Daniele Pellegrino +6 more

Broadband single photons are usually considered not to couple efficiently to atomic gases because of the large mismatch in bandwidth. Contrary to this intuitive picture, here we demonstrate that the interaction of ultrashort single photons with a dense resonant atomic sample deeply modifies the temporal shape of their wave packet mode without degrading their nonclassical character, and effectively generates zero-area single-photon pulses. This is a clear signature of strong transient coupling between single broadband (THz-level) light quanta and atoms, with intriguing fundamental implications and possible new applications to the storage of quantum information.

arXiv:1506.00523•Physical Review Letters•Jan 13, 2016•26 citations

Efficient Interface between Ultrafast and Nanosecond Optical Quantum Systems

Filip Sośnicki, Michał Mikołajczyk, Ali Golestani +1 more

A promising approach to realize a quantum internet [1] is to use a hybrid quantum network - a network composed of many different quantum devices, such as quantum emitters, quantum repeaters, or quantum gates, interconnected via photonic links. However, such a wide variety of quantum devices tends to be spectrally incompatible. Especially, the challenge arises to interface different single-photon spectral bandwidths with high efficiency. In particular, an important link is bridging the ultrafast optics with hundreds of GHz spectral bandwidths with nanosecond timescales of single-photon pulses, hence MHz-wide spectra. Such an interface corresponds, e.g., to coupling a single photon produced in a commonly used bulk spontaneous parametric down-conversion (SPDC) photon sources to atomic-based quantum memories. The already demonstrated spectral compression techniques, based mostly on optical nonlinearities, operate only in the above GHz regime and are not suitable for this task [2].

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•Jun 26, 2023•0 citations

Creation and Detection of Single Photons

Hatim Azzouz

A growing number of technologies employ quantum properties in order to produce solutions that surpass the performance of conventional devices, or to execute operations that are fundamentally impossible with classical systems alone. In the field of optical quantum information science, photons are utilized to encode, communicate and manipulate information, making them vitally important. While photon production always constitutes the first step in any optical experiment, in the field of quantum information science, the recording of data through the process of photon detection is an equally crucial final step. This thesis deals with both the single photons generation (based on diamond color defects) and their detection, utilizing a novel type of superconducting detectors. In particular, part one of this thesis is devoted to the construction of custom designed microscope setup, and the development of laboratory experiments, to enable the generation of single photons as well as the investigation of the optical and spin properties of diamond color centers. Confocal microscopy is used for this purpose, as it allows for the identification and addressing of individual color centers that emit only single photons. This microscope also feature an integrated self-built microwave and magnetic hardware setup, which allows for a wide range of spin environment spectroscopy studies. Single photon emission is demonstrated through both photon anti-bunching and Rabi oscillations at room temperature. The second part of the thesis offers an exploration of superconducting single photon detectors through experiment. Since electronics are an essential part of these detectors, the possibility of using a novel alternative scheme based on capacitive readout combined with fast gating to enable simplified readout is demonstrated. This scheme overcomes the limitations of conventional readout schemes, which require large bandwidth amplification and complex counting electronics. Besides photon detection, the capabilities of these detectors are also expanded to include high-energy particles in the MeV energy range, and the detectors are demonstrated to not only detect single α- and β-particles, but to do so with near unity efficiency. Finally, a multipurpose testing station for superconducting detectors is demonstrated with a central objective of optimizing the coupling efficiency of light to the active area of the detector, as well as to allow for a fast exchange of the optical fiber, thereby facilitating an efficient characterization of the detector. The optimization of this coupling efficiency was demonstrated through proof-of-principle experiments.

•Jan 1, 2016•1 citation

Zero Area Single Photons

L.S. Costanzo, A. S. Coelho, Daniele Pellegrino +6 more

Zero area single photons are generated through the resonant interaction of a parametric-down-conversion single photon with a dense atomic ensemble. This indicates a new pathway for developing a quantum memory for broadband single photons.

Latin America Optics and Photonics Conference•Jan 1, 2016•0 citations

Quantum networks based on single atoms in optical cavities

Stephan Ritter, Christian Nölleke, Carolin Hahn +7 more

The distribution of quantum information as well as the utilization of non-locality are at the heart of quantum networks, which show great promise for future applications like quantum communication, distributed quantum computing and quantum metrology. Their practical realization however is a formidable challenge. On the one hand, the state of the respective quantum system has to be under perfect control, ideally in all degrees of freedom. This requires low decoherence, i.e. minimal interaction with the environment. But at the same time, strong, tailored interactions are required to enable all envisioned processing tasks. In this respect, single atoms and photons are the ideal building blocks of a quantum network. Atoms can act as stationary nodes as they are long-lived and their interaction with the environment is weak, while their external and internal degree of freedom can precisely be controlled and manipulated. Photons can be transmitted over larger distances using existing fiber technology and do not mutually interact.

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•May 1, 2013•0 citations

Interfacing transitions of different alkali atoms and telecom bands using one narrowband photon pair source

Gerhard Schunk, Ulrich Vogl, Dmitry Strekalov +7 more

Quantum information technology strongly relies on coupling of optical photons with narrowband quantum systems, such as quantum dots, color centers, and atomic systems. This coupling requires matching the optical wavelength and bandwidth to the desired system, which presents a considerable problem for most available sources of quantum light. Here we demonstrate coupling of alkali dipole transitions with a tunable source of photon pairs. Our source is based on spontaneous parametric down-conversion in a triply-resonant whispering-gallery mode resonator. For this, we have developed novel wavelength tuning mechanisms, which allow for a coarse tuning to either cesium or rubidium wavelength with subsequent continuous fine-tuning to the desired transition. As a demonstration of the functionality of the source, we performed a heralded single photon measurement of the atomic decay. We present a major advance in controlling the spontaneous down-conversion process, which makes our bright source of single photons now compatible with a plethora of narrow-band resonant systems.

arXiv:1505.06141•Optica•Aug 24, 2015•61 citations
Single photons are ideal information carriers, but their limited interaction among themselves and with the surrounding environment poses a major challenge for developing a completely optical quantum processor. One possible solution lies in hybrid photon-atom approaches, but common sense suggests that an efficient coupling can be achieved only with correspondingly narrowband resonant single photons, and that ultrashort single photons with bandwidths in the THz range would be useless for this purpose given their very weak interaction with atoms. In recent experiments, we have shown that, against common intuition, a single photon of extremely short duration, and thus possessing a wide range of different colors, can still strongly interact with very monochromatic atoms.
Broadband single photons are usually considered not to couple efficiently to atomic gases because of the large mismatch in bandwidth. Contrary to this intuitive picture, here we demonstrate that the interaction of ultrashort single photons with a dense resonant atomic sample deeply modifies the temporal shape of their wave packet mode without degrading their nonclassical character, and effectively generates zero-area single-photon pulses. This is a clear signature of strong transient coupling between single broadband (THz-level) light quanta and atoms, with intriguing fundamental implications and possible new applications to the storage of quantum information.
A promising approach to realize a quantum internet [1] is to use a hybrid quantum network - a network composed of many different quantum devices, such as quantum emitters, quantum repeaters, or quantum gates, interconnected via photonic links. However, such a wide variety of quantum devices tends to be spectrally incompatible. Especially, the challenge arises to interface different single-photon spectral bandwidths with high efficiency. In particular, an important link is bridging the ultrafast optics with hundreds of GHz spectral bandwidths with nanosecond timescales of single-photon pulses, hence MHz-wide spectra. Such an interface corresponds, e.g., to coupling a single photon produced in a commonly used bulk spontaneous parametric down-conversion (SPDC) photon sources to atomic-based quantum memories. The already demonstrated spectral compression techniques, based mostly on optical nonlinearities, operate only in the above GHz regime and are not suitable for this task [2].
A growing number of technologies employ quantum properties in order to produce solutions that surpass the performance of conventional devices, or to execute operations that are fundamentally impossible with classical systems alone. In the field of optical quantum information science, photons are utilized to encode, communicate and manipulate information, making them vitally important. While photon production always constitutes the first step in any optical experiment, in the field of quantum information science, the recording of data through the process of photon detection is an equally crucial final step. This thesis deals with both the single photons generation (based on diamond color defects) and their detection, utilizing a novel type of superconducting detectors. In particular, part one of this thesis is devoted to the construction of custom designed microscope setup, and the development of laboratory experiments, to enable the generation of single photons as well as the investigation of the optical and spin properties of diamond color centers. Confocal microscopy is used for this purpose, as it allows for the identification and addressing of individual color centers that emit only single photons. This microscope also feature an integrated self-built microwave and magnetic hardware setup, which allows for a wide range of spin environment spectroscopy studies. Single photon emission is demonstrated through both photon anti-bunching and Rabi oscillations at room temperature. The second part of the thesis offers an exploration of superconducting single photon detectors through experiment. Since electronics are an essential part of these detectors, the possibility of using a novel alternative scheme based on capacitive readout combined with fast gating to enable simplified readout is demonstrated. This scheme overcomes the limitations of conventional readout schemes, which require large bandwidth amplification and complex counting electronics. Besides photon detection, the capabilities of these detectors are also expanded to include high-energy particles in the MeV energy range, and the detectors are demonstrated to not only detect single α- and β-particles, but to do so with near unity efficiency. Finally, a multipurpose testing station for superconducting detectors is demonstrated with a central objective of optimizing the coupling efficiency of light to the active area of the detector, as well as to allow for a fast exchange of the optical fiber, thereby facilitating an efficient characterization of the detector. The optimization of this coupling efficiency was demonstrated through proof-of-principle experiments.
The distribution of quantum information as well as the utilization of non-locality are at the heart of quantum networks, which show great promise for future applications like quantum communication, distributed quantum computing and quantum metrology. Their practical realization however is a formidable challenge. On the one hand, the state of the respective quantum system has to be under perfect control, ideally in all degrees of freedom. This requires low decoherence, i.e. minimal interaction with the environment. But at the same time, strong, tailored interactions are required to enable all envisioned processing tasks. In this respect, single atoms and photons are the ideal building blocks of a quantum network. Atoms can act as stationary nodes as they are long-lived and their interaction with the environment is weak, while their external and internal degree of freedom can precisely be controlled and manipulated. Photons can be transmitted over larger distances using existing fiber technology and do not mutually interact.
Quantum information technology strongly relies on coupling of optical photons with narrowband quantum systems, such as quantum dots, color centers, and atomic systems. This coupling requires matching the optical wavelength and bandwidth to the desired system, which presents a considerable problem for most available sources of quantum light. Here we demonstrate coupling of alkali dipole transitions with a tunable source of photon pairs. Our source is based on spontaneous parametric down-conversion in a triply-resonant whispering-gallery mode resonator. For this, we have developed novel wavelength tuning mechanisms, which allow for a coarse tuning to either cesium or rubidium wavelength with subsequent continuous fine-tuning to the desired transition. As a demonstration of the functionality of the source, we performed a heralded single photon measurement of the atomic decay. We present a major advance in controlling the spontaneous down-conversion process, which makes our bright source of single photons now compatible with a plethora of narrow-band resonant systems.