Single-photon emission from single-electron transport in a SAW-driven lateral light-emitting diode

Abstract

Single-photon sources are essential building blocks in quantum photonic networks, where quantum-mechanical properties of photons are utilised to achieve quantum technologies such as quantum cryptography and quantum computing. Most conventional solid-state single-photon sources are based on single emitters such as self-assembled quantum dots, which are created at random locations and require spectral filtering. These issues hinder the integration of a singlephoton source into a scaleable photonic quantum network for applications such as on-chip photonic quantum processors. In this work, using only regular lithography techniques on a conventional GaAs quantum well, we realise an electrically triggered single-photon source with a GHz repetition rate and without the need for spectral filtering. In this device, a single electron is carried in the potential minimum of a surface acoustic wave (SAW) and is transported to a region of holes to form an exciton. The exciton then decays and creates a single photon in a lifetime of ∼ 100 ps. This SAW-driven electroluminescence (EL) yields photon antibunching with g (2) (0) = 0.39 ± 0.05, which satisfies the common criterion for a single-photon source g (2) (0) < 0.5. Furthermore, we estimate that if a photon detector receives a SAW-driven EL signal within one SAW period, this signal has a 79%-90% chance of being a single photon. This work shows that a single-photon source can be made by combining single-electron transport and a lateral n-i-p junction. This approach makes it possible to create multiple synchronised single-photon sources at chosen positions with photon energy determined by quantum-well thickness. Compared with conventional quantum-dot-based single-photon sources, this device may be more suitable for an on-chip integrated photonic quantum network.The development of single-photon sources is important for many quantum information technologies [1][2][3], such as quantum cryptography [4][5][6], quantum communication [7][8][9], quantum metrology [10, 11], and quantum computation [12, 13]. Currently, most high-performance single-photon sources are self-assembled InGaAs-based quantum dots (QDs) [14][15][16]. However, there are several issues that may limit their integration into practical quantum photonic networks [17][18][19][20][21][22][23][24]. Firstly, in conventional growth of self-assembled QDs, the location and size of each QD are quite random. Therefore, one has to rely on statistics to create structures like optical cavities and gates around a quantum dot. This will be an issue for applications that require several deterministicallyfabricated single-photon sources on a compact chip. Secondly, it is hard to precisely control the size of a quantum dot, which will affect the single-photon energy. Hence, it is challenging to make identical QD single-photon sources, which is essential for applications like quantum computation and a quantum repeater [12,25]. Finally, in order to ensure that a neutral exciton is created in every optical or electrical excitation, the e...

Photon correlations probe the quantized nature of light emission from optoelectronic materials

“…This approach has also been used to localize the carriers and enable photon antibunching to be observed. 229,230 The concept effectively corresponds to SAW-driven electroluminescence and is particularly useful for converting the electron spin quantum state to the light polarization quantum state. In fact, by coupling vibrations to quantum emitters it is, in principle, also possible to prepare single quanta of vibrations, i.e.…”

Nonlinear coupling of phononic resonators induced by surface acoustic waves

“…clamped beams [12][13][14], pillars [15,16] or through intermodal coupling [17][18][19][20]. Over the past few years, both types of mechanical systems have been attracting renewed interest [21] and were exploited to achieve dynamic and coherent interaction with a variety of physical systems, including holes and electrons [22][23][24], quantum dots [25][26][27][28] spins [29][30][31], superconducting circuits [32][33][34][35] or and photonic devices [36][37][38][39][40]. Enhancing control over such mechanical systems at the micro-or nano-scale and in the radiofrequency regime therefore holds promises for the implementation of complex phononics-based hybrid platforms permitting high-speed operation.…”

Complex oxide acousto-electronics

“…SAWs interact with electrons and holes via a potential modulation of the conduction and valance bands of a semiconductor, respectively, and are able to transport them in the same direction, which is the direction of SAW propagation. This feature underlines the versatility of SAW-based electronic devices, in particular for exciton transport in optoelectronics applications 23,24 .…”

“…Charge transport by surface acoustic waves (SAWs) in new classes of lowdimensional materials has been extensively studied in the last few decades, in order to gain new perspectives and broaden the application areas in electronic devices and new technologies 18,39,40,52,57 , e.g. involving hybrid quantum systems 24,58 . SAWs are a form of periodic lattice deformations that propagate over the surface of a solid 10 .…”

“…SAWs are applied in several research fields and technological applications (e.g., acousto-fluidics, communication devices, quantum acoustics 24 ). The coupling between SAWs and low-dimensional structures creates the ability of transporting electrons with acoustic waves and could underpin the development of hybrid electronics, in which electronic and mechanical (acoustic) states may couple and hence, allow for the manipulation of information with different degrees of freedom.…”