Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Three components on one chip

06.12.2018

Scientists at the University of Stuttgart and the Karlsruhe Institute of Technology (KIT) succeed in important further development on the way to quantum Computers.

Quantum computers one day should be able to solve certain computing problems much faster than a classical computer. One of the most promising approaches is based on the utilization of single photons to carry and process quantum information.


Photonic circuit in which single photons are emitted, guided and split into two waveguide-arms.

University of Stuttgart/Mario Schwartz

Scientists of the University of Stuttgart and the Karlsruhe Institute of Technology (KIT) were now able to integrate three necessary main components (single-photon source, beamsplitters and single-photon detectors) on a single chip and operate it on the single-photon level.

This experiment demonstrates the functionality of the basic components for a scalable system for photon-based quantum information processes. The results got published in Nano Letters.

In contrast to the widespread silicon technology, the experiment was implemented on a gallium arsenide (GaAs) platform, allowing the direct integration of nanometer-sized structures, called quantum dots (QDs), which can serve as efficient on-demand sources of single photons.

In addition, GaAs allows guiding these single photons to optical logic circuits and to special on-chip detectors made of superconducting nanowires. In the experiment, single photons emitted by an optically pumped quantum dot were guided inside a photonic waveguide and divided by an on-chip beamsplitter into two waveguide-arms, each equipped with a detector.

“One of the challenges so far in this type of fully on-chip experiment was the close proximity of the excitation laser to the on-chip detectors”, explains Mario Schwartz.

The PhD student from the Institute of Semiconductor Optics and Functional Interfaces (IHFG), University of Stuttgart, was working over the last years on the realization of a proof-of-principle experiment to show the feasibility of combining all main components on one single photonic chip.

The project was realized in close collaboration with the PhD student Ekkehart Schmidt from the KIT, who is an expert for the design and implementation of the on-chip detectors. “The detectors cannot distinguish photons coming from the laser and photons coming from the quantum dot, leading to undesirable detection events”, Schmidt further points out.

The scientists were able to significantly reduce the influence of the laser photons by implementing reflecting metal layers on the chip. This idea allowed the verification of the quantum nature of the QD emission by using only the on-chip components.

“The successful experiment is an important step forward and demonstrates the potential of fully integrated photonic circuits with all main components being implemented on a single chip. We foresee clear possibilities of increasing the device complexity in the near future” says Prof. Dr. Peter Michler, director of the IHFG, University of Stuttgart.

Wissenschaftliche Ansprechpartner:

Prof. Dr. Peter Michler, Mario Schwartz, Florian Hornung, University of Stuttgart, Institute of Semiconductor Optics and Functional Interfaces (IHFG), Tel.:+49 (0)711/685-64660, p.michler@ihfg.uni-stuttgart.de

Originalpublikation:

Mario Schwartz, Ekkehart Schmidt, Ulrich Rengstl, Florian Hornung, Stefan Hepp, Simone L. Portalupi, Konstantin llin, Michael Jetter, Michael Siegel, and Peter Michler: Fully On-Chip Single-Photon Hanbury-Brown and Twiss Experiment on a Monolithic Semiconductor–Superconductor Platform, Nano Letters, 2018, 18 (11), pp 6892–6897

Weitere Informationen:

https://pubs.acs.org/doi/10.1021/acs.nanolett.8b02794

Andrea Mayer-Grenu | idw - Informationsdienst Wissenschaft

More articles from Information Technology:

nachricht 5G is smartening up production
23.08.2019 | Fraunhofer-Institut für Produktionstechnologie IPT

nachricht Software for diagnostics and fail-safe operation of robots developed at FEFU
23.08.2019 | Far Eastern Federal University

All articles from Information Technology >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Hamburg and Kiel researchers observe spontaneous occurrence of skyrmions in atomically thin cobalt films

Since their experimental discovery, magnetic skyrmions - tiny magnetic knots - have moved into the focus of research. Scientists from Hamburg and Kiel have now been able to show that individual magnetic skyrmions with a diameter of only a few nanometres can be stabilised in magnetic metal films even without an external magnetic field. They report on their discovery in the journal Nature Communications.

The existence of magnetic skyrmions as particle-like objects was predicted 30 years ago by theoretical physicists, but could only be proven experimentally in...

Im Focus: Physicists create world's smallest engine

Theoretical physicists at Trinity College Dublin are among an international collaboration that has built the world's smallest engine - which, as a single calcium ion, is approximately ten billion times smaller than a car engine.

Work performed by Professor John Goold's QuSys group in Trinity's School of Physics describes the science behind this tiny motor.

Im Focus: Quantum computers to become portable

Together with the University of Innsbruck, the ETH Zurich and Interactive Fully Electrical Vehicles SRL, Infineon Austria is researching specific questions on the commercial use of quantum computers. With new innovations in design and manufacturing, the partners from universities and industry want to develop affordable components for quantum computers.

Ion traps have proven to be a very successful technology for the control and manipulation of quantum particles. Today, they form the heart of the first...

Im Focus: Towards an 'orrery' for quantum gauge theory

Experimental progress towards engineering quantized gauge fields coupled to ultracold matter promises a versatile platform to tackle problems ranging from condensed-matter to high-energy physics

The interaction between fields and matter is a recurring theme throughout physics. Classical cases such as the trajectories of one celestial body moving in the...

Im Focus: A miniature stretchable pump for the next generation of soft robots

Soft robots have a distinct advantage over their rigid forebears: they can adapt to complex environments, handle fragile objects and interact safely with humans. Made from silicone, rubber or other stretchable polymers, they are ideal for use in rehabilitation exoskeletons and robotic clothing. Soft bio-inspired robots could one day be deployed to explore remote or dangerous environments.

Most soft robots are actuated by rigid, noisy pumps that push fluids into the machines' moving parts. Because they are connected to these bulky pumps by tubes,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

The power of thought – the key to success: CYBATHLON BCI Series 2019

16.08.2019 | Event News

4th Hybrid Materials and Structures 2020 28 - 29 April 2020, Karlsruhe, Germany

14.08.2019 | Event News

What will the digital city of the future look like? City Science Summit on 1st and 2nd October 2019 in Hamburg

12.08.2019 | Event News

 
Latest News

Making small intestine endoscopy faster with a pill-sized high-tech camera

23.08.2019 | Medical Engineering

More reliable operation offshore wind farms

23.08.2019 | Power and Electrical Engineering

Tracing the evolution of vision

23.08.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>