Quantum Researchers Develop Method to Measure Photocurrents Flow in 2D

January 16, 2020

Jan. 16, 2020 — Quantum researchers at the University of Chicago have developed a new method to measure how photocurrents flow in a 2D material — a result that could have implications for developing quantum sensors and next-generation electronics.

By using quantum sensors to visualize the magnetic field in extremely thin molybdenum disulfide (MoS2) — a material just three atoms thick — researchers in David Awschalom’s group at the University of Chicago discovered just how photocurrents (electric currents induced by light) flowed in the material — in this case, surprisingly, in a vortex around the laser. This ultra-sensitive method of measuring such currents in a two-dimensional material, which is a substance with a thickness of a new nanometers or less, will help researchers better understand the material in the hopes of eventually using it to create flexible electronics and solar cells. The results were published January 6 in the journal Physical Review X.

PhD student Paul Jerger adjusts the mount that lets researchers rotate and position their magnet. Image courtesy of Jonathan Karsch, CQE. 

“The ability to observe electronic behavior that is invisible to traditional measurements opens new avenues for scientific study, and ultimately helps us design efficient quantum technologies,” said principal investigator David Awschalom, the Liew Family Professor in Molecular Engineering, senior scientist at Argonne National Laboratory, and director of the Chicago Quantum Exchange. “This sensitive measurement technique allows us to explore phenomena at the atomic scale and develop new devices for quantum sensing and communication.

Measuring currents in extremely thin materials

To make the measurement, Awschalom and his team placed MoS2 on a nitrogen-vacancy center, which is a defect in a diamond where a nitrogen atom sits next to a vacant site in the diamond’s lattice. These spots can be used to study electronic and nuclear spin phenomena.

The team then shined a red laser onto the material to see if they could detect any temporary magnetic disturbances (that they hypothesized the laser might cause). But instead of magnetic disturbances, they detected strong photocurrents, which can result when light is shined onto a material. These photocurrents produce magnetic fields as they flow. Photocurrents are the basis behind the technology in digital cameras, solar cells, and fiber-optic networks.

The researchers were surprised to discover the photocurrents traveling in a vortex around the laser — a shape that would be impossible to detect with other techniques.

Traditional methods to measure how photocurrents flow through MoS2 are difficult to perform and are often incorrect. Understanding this phenomenon is important to develop potentially flexible and transparent electronics from MoS2 and other 2D materials.

“We are much happier that we found photocurrents instead of the magnetic disturbances we were looking for,” said Paul Jerger, a graduate student in Awschalom’s lab who conducted the research with former postdoctoral fellow Brian Zhou, who is now at Boston College. “Understanding photocurrents will help us better understand the electrical properties of materials like this, with the hopes of using them for electronics like digital cameras or solar cells.”

Creating more compact quantum devices

The finding could pave the way for better experimental setups in the lab, where the nitrogen-vacancy centers are used to conduct quantum operations. It will also be useful for understanding how photocurrents are generated and propagated, which could enable researchers to use thin materials for digital cameras, solar cells, or even on-demand magnetic fields that don’t require any electrical wires.

Next the team hopes to adapt the process to measure photocurrents at room temperature, and to try to apply this technique to measure photocurrents in other thin materials, like graphene.

“As we synthesize quantum materials of the highest quality, we ideally want to measure them without making disruptive electrical connections,” said Jiwoong Park, professor of chemistry and joint appointee at Argonne National Laboratory, whose group created the MoS2 used in the study. “This new technique allows us to do that, paving the way to develop novel quantum materials in industrial-scale processes.”

Other authors on the paper include Kan-Heng Lee, Masaya Fukami, and Fauzia Mujid.

About the Chicago Quantum Exchange

The Chicago Quantum Exchange (CQE) is an intellectual hub and community of researchers with the common goal of advancing academic and industrial efforts in the science and engineering of quantum information across CQE members, partners, and our region. The hub aims to promote the exploration of quantum information technologies and the development of new applications. The CQE facilitates interactions between research groups of its member and partner institutions and provides an avenue for developing and fostering collaborations, joint projects, and information exchange.


Source: Chicago Quantum Exchange

Subscribe to HPCwire's Weekly Update!

Be the most informed person in the room! Stay ahead of the tech trends with industry updates delivered to you every week!

A Big Memory Nvidia GH200 Next to Your Desk: Closer Than You Think

February 22, 2024

Students of the microprocessor may recall that the original 8086/8088 processors did not have floating point units. The motherboard often had an extra socket for an optional 8087 math coprocessor. The math coprocessor ma Read more…

IonQ Reports Advance on Path to Networked Quantum Computing

February 22, 2024

IonQ reported reaching a milestone in its efforts to use entangled photon-ion connectivity to scale its quantum computers. IonQ’s quantum computers are based on trapped ions which feature long coherence times and qubit Read more…

Apple Rolls out Post Quantum Security for iOS

February 21, 2024

Think implementing so-called Post Quantum Cryptography (PQC) isn't important because quantum computers able to decrypt current RSA codes don’t yet exist? Not Apple. Today the consumer electronics giant started rolling Read more…

GenAI Having Major Impact on Data Culture, Survey Says

February 21, 2024

While 2023 was the year of GenAI, the adoption rates for GenAI did not match expectations. Most organizations are continuing to invest in GenAI but are yet to derive any substantial value from it. However, the GenAI hyp Read more…

QED-C Issues New Quantum Benchmarking Paper

February 20, 2024

The Quantum Economic Development Consortium last week released a new paper on benchmarking – Quantum Algorithm Exploration using Application-Oriented Performance Benchmarks – that builds on earlier work and is an eff Read more…

AWS Solution Channel

Shutterstock 2283618597

Deep-dive into Ansys Fluent performance on Ansys Gateway powered by AWS

Today, we’re going to deep-dive into the performance and associated cost of running computational fluid dynamics (CFD) simulations on AWS using Ansys Fluent through the Ansys Gateway powered by AWS (or just “Ansys Gateway” for the rest of this post). Read more…

Atom Computing Reports Advance in Scaling Up Neutral Atom Qubit Arrays

February 15, 2024

The scale-up challenge facing quantum computing (QC) is daunting and varied. It’s commonly held that 1 million qubits (or more) will be needed to deliver practical fault tolerant QC. It’s also a varied challenge beca Read more…

A Big Memory Nvidia GH200 Next to Your Desk: Closer Than You Think

February 22, 2024

Students of the microprocessor may recall that the original 8086/8088 processors did not have floating point units. The motherboard often had an extra socket fo Read more…

Apple Rolls out Post Quantum Security for iOS

February 21, 2024

Think implementing so-called Post Quantum Cryptography (PQC) isn't important because quantum computers able to decrypt current RSA codes don’t yet exist? Not Read more…

QED-C Issues New Quantum Benchmarking Paper

February 20, 2024

The Quantum Economic Development Consortium last week released a new paper on benchmarking – Quantum Algorithm Exploration using Application-Oriented Performa Read more…

The Pulse of HPC: Tracking 4.5 Million Heartbeats of 3D Coronary Flow

February 15, 2024

Working in Duke University's Randles Lab, Cyrus Tanade, a National Science Foundation graduate student fellow and Ph.D. candidate in biomedical engineering, is Read more…

It Doesn’t Get Much SWEETER: The Winter HPC Computing Festival in Corpus Christi

February 14, 2024

(Main Photo by Visit Corpus Christi CrowdRiff) Texas A&M University's High-Performance Research Computing (HPRC) team hosted the "SWEETER Winter Comput Read more…

Q-Roundup: Diraq’s War Chest, DARPA’s Bet on Topological Qubits, Citi/Classiq Explore Optimization, WEF’s Quantum Blueprint

February 13, 2024

Yesterday, Australian start-up Diraq added $15 million to its war chest (now $120 million) to build a fault tolerant computer based on quantum dots. Last week D Read more…

2024 Winter Classic: Razor Thin Margins in HPL/HPCG

February 12, 2024

The first task for the 11 teams in the 2024 Winter Classic student cluster competition was to run and optimize the LINPACK and HPCG benchmarks. As usual, the Read more…

2024 Winter Classic: We’re Back!

February 9, 2024

The fourth edition of the Winter Classic Invitational Student Cluster Competition is up and running. This year, we have 11 teams of eager students representin Read more…

CORNELL I-WAY DEMONSTRATION PITS PARASITE AGAINST VICTIM

October 6, 1995

Ithaca, NY --Visitors to this year's Supercomputing '95 (SC'95) conference will witness a life-and-death struggle between parasite and victim, using virtual Read more…

SGI POWERS VIRTUAL OPERATING ROOM USED IN SURGEON TRAINING

October 6, 1995

Surgery simulations to date have largely been created through the development of dedicated applications requiring considerable programming and computer graphi Read more…

U.S. Will Relax Export Restrictions on Supercomputers

October 6, 1995

New York, NY -- U.S. President Bill Clinton has announced that he will definitely relax restrictions on exports of high-performance computers, giving a boost Read more…

Dutch HPC Center Will Have 20 GFlop, 76-Node SP2 Online by 1996

October 6, 1995

Amsterdam, the Netherlands -- SARA, (Stichting Academisch Rekencentrum Amsterdam), Academic Computing Services of Amsterdam recently announced that it has pur Read more…

Cray Delivers J916 Compact Supercomputer to Solvay Chemical

October 6, 1995

Eagan, Minn. -- Cray Research Inc. has delivered a Cray J916 low-cost compact supercomputer and Cray's UniChem client/server computational chemistry software Read more…

NEC Laboratory Reviews First Year of Cooperative Projects

October 6, 1995

Sankt Augustin, Germany -- NEC C&C (Computers and Communication) Research Laboratory at the GMD Technopark has wrapped up its first year of operation. Read more…

Sun and Sybase Say SQL Server 11 Benchmarks at 4544.60 tpmC

October 6, 1995

Mountain View, Calif. -- Sun Microsystems, Inc. and Sybase, Inc. recently announced the first benchmark results for SQL Server 11. The result represents a n Read more…

New Study Says Parallel Processing Market Will Reach $14B in 1999

October 6, 1995

Mountain View, Calif. -- A study by the Palo Alto Management Group (PAMG) indicates the market for parallel processing systems will increase at more than 4 Read more…

Leading Solution Providers

Contributors

CORNELL I-WAY DEMONSTRATION PITS PARASITE AGAINST VICTIM

October 6, 1995

Ithaca, NY --Visitors to this year's Supercomputing '95 (SC'95) conference will witness a life-and-death struggle between parasite and victim, using virtual Read more…

SGI POWERS VIRTUAL OPERATING ROOM USED IN SURGEON TRAINING

October 6, 1995

Surgery simulations to date have largely been created through the development of dedicated applications requiring considerable programming and computer graphi Read more…

U.S. Will Relax Export Restrictions on Supercomputers

October 6, 1995

New York, NY -- U.S. President Bill Clinton has announced that he will definitely relax restrictions on exports of high-performance computers, giving a boost Read more…

Dutch HPC Center Will Have 20 GFlop, 76-Node SP2 Online by 1996

October 6, 1995

Amsterdam, the Netherlands -- SARA, (Stichting Academisch Rekencentrum Amsterdam), Academic Computing Services of Amsterdam recently announced that it has pur Read more…

Cray Delivers J916 Compact Supercomputer to Solvay Chemical

October 6, 1995

Eagan, Minn. -- Cray Research Inc. has delivered a Cray J916 low-cost compact supercomputer and Cray's UniChem client/server computational chemistry software Read more…

NEC Laboratory Reviews First Year of Cooperative Projects

October 6, 1995

Sankt Augustin, Germany -- NEC C&C (Computers and Communication) Research Laboratory at the GMD Technopark has wrapped up its first year of operation. Read more…

Sun and Sybase Say SQL Server 11 Benchmarks at 4544.60 tpmC

October 6, 1995

Mountain View, Calif. -- Sun Microsystems, Inc. and Sybase, Inc. recently announced the first benchmark results for SQL Server 11. The result represents a n Read more…

New Study Says Parallel Processing Market Will Reach $14B in 1999

October 6, 1995

Mountain View, Calif. -- A study by the Palo Alto Management Group (PAMG) indicates the market for parallel processing systems will increase at more than 4 Read more…

  • arrow
  • Click Here for More Headlines
  • arrow
HPCwire