• Latest
  • Trending
  • All
  • Capacitors
  • Resistors
  • Inductors
  • Filters
  • Fuses
  • Non-linear Passives
  • Applications
  • Integrated Passives
  • Oscillators
  • Passive Sensors
  • New Technologies
  • Aerospace & Defence
  • Automotive
  • Industrial
  • Market & Supply Chain
  • Medical
  • RF & Microwave
  • Telecommunication
The magnetic field is varied along the vertical axis. Horizontal Yellow streaks show propagation of Brown-Zak fermions, propagating along straight trajectories with high mobility (low resistance), whereas slanted indigo lines show the cyclotron motion around Brown-Zak fermions. The slope of these lines enabled us to get the degeneracy (and find an additional quantum number) of these new quasiparticles. Credit: Julien Barrier, University of Manchester

University of Manchester Discovers ‘radically different’ Physics in Graphene that Can Lead to Development of New Electronic Devices

16.11.2020

Euroquartz Releases SMD VCXO Low Jitter HF Oscillator

26.5.2022
Crusher at the Wodgina lithium mine in Western Australia. Image courtesy of Mineral Resources.

Restart of Wodgina Mine is a Good News for Tantalum and Lithium Supply Chain

26.5.2022

Vishay Introduces Highest Energy Density Wet Tantalum Capacitors

26.5.2022

Impact of Ripple Current on Aluminum Electrolytic Capacitors Lifetime

25.5.2022
  • Home
  • Privacy Policy
  • EPCI Advertisement & Membership
  • About
No Result
View All Result
NEWSLETTER
Passive Components Blog
  • Home
  • NewsFilter
    • All
    • Aerospace & Defence
    • Antenna
    • Applications
    • Automotive
    • Capacitors
    • Filters
    • Fuses
    • Inductors
    • Industrial
    • Integrated Passives
    • Market & Supply Chain
    • Medical
    • New Materials & Supply
    • New Technologies
    • Non-linear Passives
    • Oscillators
    • Passive Sensors
    • Resistors
    • RF & Microwave
    • Telecommunication

    Euroquartz Releases SMD VCXO Low Jitter HF Oscillator

    Crusher at the Wodgina lithium mine in Western Australia. Image courtesy of Mineral Resources.

    Restart of Wodgina Mine is a Good News for Tantalum and Lithium Supply Chain

    Vishay Introduces Highest Energy Density Wet Tantalum Capacitors

    Impact of Ripple Current on Aluminum Electrolytic Capacitors Lifetime

    A set of printed sample cubes showcasing the effects of laser power and print speed on the magnetic core structures. Image source: Tallinn University of Technology

    Researchers 3D Printed Superior Soft Magnetic Cores with Laser Additive Process

    TDK Introduces Improved Performance PFC Capacitors

    Yageo Venture to Acquire 30% of APEC and Step Into Semiconductor MOSFET Business

    Vishay NTC Thermistor LTspice Simulation for PID Optimization; Vishay Webinar

    Stackpole Presents High Current Metal Shunt Resistors

    Trending Tags

    • Ripple Current
    • RF
    • Leakage Current
    • Tantalum vs Ceramic
    • Snubber
    • Low ESR
    • Feedthrough
    • Derating
    • Dielectric Constant
    • New Products
    • Market Reports
  • VideoFilter
    • All
    • Antenna videos
    • Capacitor videos
    • Filter videos
    • Fuse videos
    • Inductor videos
    • Non-linear passives videos
    • Oscillator videos
    • Passive sensors videos
    • Resistor videos
    • Sensors

    Vishay NTC Thermistor LTspice Simulation for PID Optimization; Vishay Webinar

    Coverlay – More than a Flexible Soldermask Substitute; WE Webinar

    Soldering THT Components by SMD Reflow Assembly; WE Webinar

    Strain Gage Resistive Sensor Simulation; Vishay Video

    EMC Filters Explained – from Component to Design; WE Webinar

    How to Avoid EMI Noise on Data Cable by Isolated Power Module; WE askLorandt Video

    Introduction to Wireless Power Transfer; WE Webinar

    How to Pass Conducted Emissions Using Line Filters; WE Webinar

    EMI Debugging of a Low Power Buck Converter; WE Webinar

    Trending Tags

    • Capacitors explained
    • Inductors explained
    • Resistors explained
    • Filters explained
    • Application Video Guidelines
    • EMC
    • New Products
    • Ripple Current
    • Simulation
    • Tantalum vs Ceramic
  • Knowledge Blog
  • Preferred Suppliers
  • Who is Who
  • Events
  • Home
  • NewsFilter
    • All
    • Aerospace & Defence
    • Antenna
    • Applications
    • Automotive
    • Capacitors
    • Filters
    • Fuses
    • Inductors
    • Industrial
    • Integrated Passives
    • Market & Supply Chain
    • Medical
    • New Materials & Supply
    • New Technologies
    • Non-linear Passives
    • Oscillators
    • Passive Sensors
    • Resistors
    • RF & Microwave
    • Telecommunication

    Euroquartz Releases SMD VCXO Low Jitter HF Oscillator

    Crusher at the Wodgina lithium mine in Western Australia. Image courtesy of Mineral Resources.

    Restart of Wodgina Mine is a Good News for Tantalum and Lithium Supply Chain

    Vishay Introduces Highest Energy Density Wet Tantalum Capacitors

    Impact of Ripple Current on Aluminum Electrolytic Capacitors Lifetime

    A set of printed sample cubes showcasing the effects of laser power and print speed on the magnetic core structures. Image source: Tallinn University of Technology

    Researchers 3D Printed Superior Soft Magnetic Cores with Laser Additive Process

    TDK Introduces Improved Performance PFC Capacitors

    Yageo Venture to Acquire 30% of APEC and Step Into Semiconductor MOSFET Business

    Vishay NTC Thermistor LTspice Simulation for PID Optimization; Vishay Webinar

    Stackpole Presents High Current Metal Shunt Resistors

    Trending Tags

    • Ripple Current
    • RF
    • Leakage Current
    • Tantalum vs Ceramic
    • Snubber
    • Low ESR
    • Feedthrough
    • Derating
    • Dielectric Constant
    • New Products
    • Market Reports
  • VideoFilter
    • All
    • Antenna videos
    • Capacitor videos
    • Filter videos
    • Fuse videos
    • Inductor videos
    • Non-linear passives videos
    • Oscillator videos
    • Passive sensors videos
    • Resistor videos
    • Sensors

    Vishay NTC Thermistor LTspice Simulation for PID Optimization; Vishay Webinar

    Coverlay – More than a Flexible Soldermask Substitute; WE Webinar

    Soldering THT Components by SMD Reflow Assembly; WE Webinar

    Strain Gage Resistive Sensor Simulation; Vishay Video

    EMC Filters Explained – from Component to Design; WE Webinar

    How to Avoid EMI Noise on Data Cable by Isolated Power Module; WE askLorandt Video

    Introduction to Wireless Power Transfer; WE Webinar

    How to Pass Conducted Emissions Using Line Filters; WE Webinar

    EMI Debugging of a Low Power Buck Converter; WE Webinar

    Trending Tags

    • Capacitors explained
    • Inductors explained
    • Resistors explained
    • Filters explained
    • Application Video Guidelines
    • EMC
    • New Products
    • Ripple Current
    • Simulation
    • Tantalum vs Ceramic
  • Knowledge Blog
  • Preferred Suppliers
  • Who is Who
  • Events
No Result
View All Result
Passive Components Blog
No Result
View All Result

University of Manchester Discovers ‘radically different’ Physics in Graphene that Can Lead to Development of New Electronic Devices

16.11.2020
Reading Time: 4 mins read
0 0
The magnetic field is varied along the vertical axis. Horizontal Yellow streaks show propagation of Brown-Zak fermions, propagating along straight trajectories with high mobility (low resistance), whereas slanted indigo lines show the cyclotron motion around Brown-Zak fermions. The slope of these lines enabled us to get the degeneracy (and find an additional quantum number) of these new quasiparticles. Credit: Julien Barrier, University of Manchester

The magnetic field is varied along the vertical axis. Horizontal Yellow streaks show propagation of Brown-Zak fermions, propagating along straight trajectories with high mobility (low resistance), whereas slanted indigo lines show the cyclotron motion around Brown-Zak fermions. The slope of these lines enabled us to get the degeneracy (and find an additional quantum number) of these new quasiparticles. Credit: Julien Barrier, University of Manchester

0
SHARES
140
VIEWS

A group of researchers led by Sir Andre Geim and Dr Alexey Berdyugin at The University of Manchester have discovered and characterised a new family of quasiparticles named ‘Brown-Zak fermions’ in graphene-based superlattices.

The team achieved this breakthrough by aligning the atomic lattice of a graphene layer to that of an insulating boron nitride sheet, dramatically changing the properties of the graphene sheet.

RelatedPosts

Euroquartz Releases SMD VCXO Low Jitter HF Oscillator

Restart of Wodgina Mine is a Good News for Tantalum and Lithium Supply Chain

Vishay Introduces Highest Energy Density Wet Tantalum Capacitors

The study follows years of successive advances in graphene-boron nitride superlattices which allowed the observation of a fractal pattern known as the Hofstadter’s butterfly – and today (Friday, November 13) the researchers report another highly surprising behaviour of particles in such structures under applied magnetic field.

“It is well known, that in a zero magnetic field, electrons move in straight trajectories and if you apply a magnetic field they start to bend and move in circles”, explain Julien Barrier and Dr Piranavan Kumaravadivel, who carried out the experimental work.

“In a graphene layer which has been aligned with the boron nitride, electrons also start to bend – but if you set the magnetic field at specific values, the electrons move in straight line trajectories again, as if there is no magnetic field anymore!”

“Such behaviour is radically different from textbook physics.” adds Dr Piranavan Kumaravadivel.

“We attribute this fascinating behaviour to the formation of novel quasiparticles at high magnetic field,” says Dr Alexey Berdyugin.  “Those quasiparticles have their own unique properties and exceptionally high mobility despite the extremely high magnetic field.”

As published in Nature Communications, the work describes how electrons behave in an ultra-high-quality superlattice of graphene with a revised framework for the fractal features of the Hofstadter’s butterfly. Fundamental improvements in graphene device fabrication and measurement techniques in the past decade have made this work possible.

A new quasiparticle

“The concept of quasiparticles is arguably one of the most important in condensed matter physics and quantum many-body systems. It was introduced by the theoretical physicist Lev Landau in the 1940s to depict collective effects as a ‘one particle excitation’,” explains Julien Barrier “They are used in a number of complex systems to account for many-body effects.”

Until now, the behaviour of collective electrons in graphene superlattices were thought in terms of the Dirac fermion, a quasiparticle that has unique properties resembling photons (particles with no mass), that replicate at high magnetic fields. However, this did not account for some experimental features, like the additional degeneracy of the states, nor did it match the finite mass of the quasiparticle in this state.

The authors propose ‘Brown-Zak fermions’ to be the family of quasiparticles existing in superlattices under high magnetic field. This is characterised by a new quantum number that can directly be measured. Interestingly, working at lower temperatures allowed them to lift the degeneracy with exchange interactions at ultra-low temperatures.

“Under the presence of a magnetic field, electrons in graphene start rotating with quantised orbits. For Brown-Zak fermions, we managed to restore a straight trajectory of tens of micrometres under high magnetic fields up to 16T (500,000 times earth’s magnetic field). Under specific conditions, the ballistic quasiparticles feel no effective magnetic field,” explain Dr Kumaravadivel and Dr Berdyugin.

High mobility of Brown Zak fermions

In an electronic system, the mobility is defined as the capacity for a particle to travel upon the application of an electrical current. High mobilities have long been the Holy Grail when fabricating 2D systems such as graphene because such materials would present additional properties (integer and fractional quantum hall effects), and potentially allow the creation of ultra-high frequency transistors, the components at the heart of a computer processor.

“For this study we prepared graphene devices that are extra-large with a very high level of purity”. says Dr Kumaravadivel. This allowed us to achieve mobilities of several millions of cm²/Vs, which means particles would travel straight across the entire device without scattering. Importantly, this was not only the case for classical Dirac fermions in graphene, but also realised for the Brown-Zak fermions reported in the work.

These Brown-Zak fermions define new metallic states, that are generic to any superlattice system, not just graphene and offers a playground for new condensed matter physics problems in other 2D material based superlattices.

Julien Barrier added “The findings are important, of course for fundamental studies in electron transport, but we believe that understanding quasiparticles in novel superlattice devices under high magnetic fields can lead to the development of new electronic devices.”

The high mobility means that a transistor made from such a device could operate at higher frequencies, allowing a processor made out of this material to perform more calculations per unit of time, resulting in a faster computer. Applying a magnetic field would usually scale down the mobility and make such a device unusable for certain applications. The high mobilities of Brown-Zak fermions at high magnetic fields open a new perspective for electronic devices operating under extreme conditions.

The paper, Long-range ballistic transport of Brown-Zak fermions in graphene superlattices, is published in Nature Communications (Friday, 13 November 2020).

Source: University of Manchester

Related Posts

A set of printed sample cubes showcasing the effects of laser power and print speed on the magnetic core structures. Image source: Tallinn University of Technology
Inductors

Researchers 3D Printed Superior Soft Magnetic Cores with Laser Additive Process

24.5.2022
22
Capacitors

GAM Introduces Tantalum and Niobium Powders for Cold Spray Applications

19.5.2022
46
Capacitors

ELOHIM Develops Ultra-Small Size High-Density Silicon Capacitors

25.4.2022
282

Popular Posts

  • Understanding High-Precision Resistor Temperature Coefficient of Resistance

    0 shares
    Share 0 Tweet 0
  • Ripple Current and its Effects on the Performance of Capacitors

    3 shares
    Share 3 Tweet 0
  • What is a Dielectric Constant of Plastic Materials ?

    4 shares
    Share 4 Tweet 0
  • Why Low ESR Matters in Capacitor Design

    0 shares
    Share 0 Tweet 0
  • Capacitor Selection for Coupling and Decoupling Applications

    28 shares
    Share 28 Tweet 0

Newsletter Subscription

 

  • Home
  • Privacy Policy
  • EPCI Advertisement & Membership
  • About

© 2021 EPCI - Premium Passive Components Educational and Information Site

No Result
View All Result
  • Home
  • News
  • Video
  • Knowledge Blog
  • Preferred Suppliers
  • Events

© 2021 EPCI - Premium Passive Components Educational and Information Site

Welcome Back!

Login to your account below

Forgotten Password?

Retrieve your password

Please enter your username or email address to reset your password.

Log In
This website uses cookies. By continuing to use this website you are giving consent to cookies being used. Visit our Privacy and Cookie Policy.