English

The LANL Laboratory in the United States has achieved a light source that generates a circularly polarized single photon stream using a quantum light emitter

80
2023-09-02 14:48:48
See translation

Los Alamos National Laboratory (LANL) has developed a method for a quantum light emitter that stacks two different atomically thin materials together to achieve a light source that produces a stream of circularly polarized single photons. These light sources can in turn be used for a variety of quantum information and communication applications.

According to Los Alamos researcher Han Htoon, the work shows that single-layer semiconductors can emit circularly polarized light without the need for an external magnetic field.

"This effect has previously only been possible with high magnetic fields generated by bulky superconducting magnets, by coupling quantum emitters to very complex nanoscale photonic structures, or by injecting spin-polarized charge carriers into the quantum emitters." Our proximity effect approach has the advantage of low manufacturing costs and high reliability."

Polarization states are a means of encoding photons, so this result is an important step in the direction of quantum cryptography, or quantum communication. "With a light source that produces a single photon stream and introduces polarization, we basically have two devices in one."

The team stacked a single-molecule thick layer of tungsten diselenide semiconductors on top of a thicker layer of magnetic nickel-phosphorus trisulfide semiconductors. Using an atomic force microscope, the team created a series of nanoscale indentations on a thin layer of material.

When the laser is focused on the pile of material, the 400 nanometer-diameter indentation created by the atom microscope tool has two effects. First, the indentation forms a "well" or "depression" in the potential energy landscape. The electrons of the tungsten diselenide monolayer fall in the depression. This stimulates the emission of a single photon from the trap.

The nanoindentation also destroys the typical magnetic properties of the underlying nickel-phosphorus trisulfide crystals, creating a local magnetic moment pointing outward from the material. This magnetic moment causes the emitted photon to be circularly polarized. To experimentally confirm this mechanism, the team first conducted high-magnetic field spectroscopy experiments in collaboration with the Pulse Field Facility at the Los Alamos National High Magnetic Field Laboratory. The team then worked with the University of Basel in Switzerland to measure the tiny magnetic field of the local magnetic moment.

The team is now exploring ways to modulate the degree of circular polarization of single photons through electronic or microwave stimulation. This ability would provide a way to encode quantum information into a stream of photons. Further coupling of the photon stream to the waveguide will provide the photonic circuit so that the photons propagate in one direction. Such circuits will become a fundamental component of an ultra-secure quantum Internet.

Source: OFweek

Related Recommendations
  • Unsupervised physical neural network empowers stacked imaging denoising algorithm

    In view of the reconstruction problem of stack imaging technology in noisy environment, Lin Nan's team from Shanghai Institute of Optics and Mechanics, Chinese Academy of Sciences, proposed an innovative method ProPtyNet based on unsupervised physical neural network, which is expected to be applied to chip CD measurement and defect detection. The article was published in Optics and lasers in engin...

    03-25
    See translation
  • German optoelectronic component manufacturer collaborates heavily to develop VCSELs lasers

    This collaboration deeply integrates the unique expertise and cutting-edge technological achievements of both companies in the field of optoelectronics, aiming to broaden the boundaries of optoelectronics innovation.EPIGAP OSA Photonics GmbH, as a leader in the research and manufacturing of optoelectronic components in Germany, is deeply rooted in multiple fields such as medical technology, indust...

    2024-08-06
    See translation
  • Researchers at the Massachusetts Institute of Technology have designed a new type of quantum light source using lead salt perovskite nanoparticles

    Most traditional quantum computing uses the spin of supercooled atoms or individual electrons as quantum bits, which form the foundation of such devices. By comparison, if light is used to replace physical entities as basic quantum bits, ordinary lenses and optical detectors can replace expensive devices to control the data input and output of quantum bits.Based on this, chemistry professors Moung...

    2023-10-09
    See translation
  • AEROTECH releases updated AUTOMATION1 motion control platform

    Aerotech is a global leader in precision motion control and automation, and every release has made the Automation1 motion control platform even stronger and more user-friendly. Version 2.5 brings TCP socket interface (test version), Automation1 MachineApps HMI development, new auxiliary module for motor settings, and improved machine settings for galvanometer laser scanning heads.Automation1 conti...

    2023-08-14
    See translation
  • The efficiency of crystalline silicon solar cells has exceeded 27% for the first time, and Longi's research results have been published in Nature

    Recently, Longi Green Energy Technology Co., Ltd. (hereinafter referred to as "Longi"), as the first unit, published a research paper titled "Silicon heterojunction back contact solar cells by laser patterning" online in the journal Nature, reporting for the first time the research results of breaking through 27% of the photoelectric conversion efficiency of crystalline silicon cells through full ...

    2024-10-18
    See translation