Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International



Home > Press > Scientists discover spin polarization induced by shear flow

Fig. 1. left: the polarization induced by the vortical flow; right: the polarization induced by the shear flow. Red and yellow arrows represent the spin and momentum directions, respectively.

CREDIT
Shuai Liu
Fig. 1. left: the polarization induced by the vortical flow; right: the polarization induced by the shear flow. Red and yellow arrows represent the spin and momentum directions, respectively. CREDIT Shuai Liu

Abstract:
Chinese researchers recently discovered a new effect that can generate spin-polarization in fluid. The new effect, which is called "shear-induced polarization (SIP)," predicts that shear flow can induce polarization in the momentum space.

Scientists discover spin polarization induced by shear flow

Beijing, China | Posted on October 1st, 2021

This research was conducted by scientists from the Institute of Modern Physics (IMP) of the Chinese Academy of Sciences (CAS), together with their collaborators at Peking University and Central China Normal University, who studied polarization induced by shear flow for the first time. Their discoveries were published in Physical Review Letters and Journal of High Energy Physics.

In flowing fluid, one may observe some special patterns of the flow field, such as those formed by the vortical flow, which rotates around a center and is related to the orbital angular momentum of the fluid. Due to spin-orbit coupling, the orbital angular momentum of the vortical flow can transfer to the spin of a particle. This vorticity-induced spin polarization has been observed in a quantum fluid.

Besides vortical flow, shear flow is also quite common in fluids. However, it is far less intuitive how shear flow is related to angular momentum. Thus, how it affects spin polarization has never been investigated before.

In this research, using relativistic many-body quantum theory and linear response theory, the researchers systematically studied spin polarization in a hydrodynamic medium. They discovered that shear flow, although not intuitively related to orbital angular momentum, also generates spin polarization in the momentum space through spin-orbit coupling.

Employing a relativistic hydrodynamic model, the researchers then investigated how this new SIP effect manifests in relativistic heavy-ion collisions. Since previous studies do not include the SIP effect, their predictions always have the opposite sign compared to experimental observations. This discrepancy is sometimes called the "spin-sign puzzle" and has bothered the research community for several years.

However, once the SIP effect is included, the strange quark polarization predicted by the theory demonstrates a pattern similar to the measured Lambda polarization in experiments.

Considering the close relationship between strange quark polarization and Lambda polarization, the current study is expected to be an essential step toward the final solution of the spin-sign puzzle.

This work was supported by the National Natural Science Foundation of China and the Strategic Priority Research Program of CAS.

####

For more information, please click here

Contacts:
Fang Liu
Institute of Modern Physics

Copyright © Chinese Academy of Sciences

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related Links

ARTICLE TITLE

Related News Press

News and information

Researchers develop artificial building blocks of life March 8th, 2024

How surface roughness influences the adhesion of soft materials: Research team discovers universal mechanism that leads to adhesion hysteresis in soft materials March 8th, 2024

Two-dimensional bimetallic selenium-containing metal-organic frameworks and their calcinated derivatives as electrocatalysts for overall water splitting March 8th, 2024

Curcumin nanoemulsion is tested for treatment of intestinal inflammation: A formulation developed by Brazilian researchers proved effective in tests involving mice March 8th, 2024

Physics

Nanoscale CL thermometry with lanthanide-doped heavy-metal oxide in TEM March 8th, 2024

Optically trapped quantum droplets of light can bind together to form macroscopic complexes March 8th, 2024

Scientists use heat to create transformations between skyrmions and antiskyrmions January 12th, 2024

Focused ion beam technology: A single tool for a wide range of applications January 12th, 2024

Govt.-Legislation/Regulation/Funding/Policy

What heat can tell us about battery chemistry: using the Peltier effect to study lithium-ion cells March 8th, 2024

Researchers’ approach may protect quantum computers from attacks March 8th, 2024

The Access to Advanced Health Institute receives up to $12.7 million to develop novel nanoalum adjuvant formulation for better protection against tuberculosis and pandemic influenza March 8th, 2024

Optically trapped quantum droplets of light can bind together to form macroscopic complexes March 8th, 2024

Possible Futures

Two-dimensional bimetallic selenium-containing metal-organic frameworks and their calcinated derivatives as electrocatalysts for overall water splitting March 8th, 2024

Curcumin nanoemulsion is tested for treatment of intestinal inflammation: A formulation developed by Brazilian researchers proved effective in tests involving mice March 8th, 2024

The Access to Advanced Health Institute receives up to $12.7 million to develop novel nanoalum adjuvant formulation for better protection against tuberculosis and pandemic influenza March 8th, 2024

Nanoscale CL thermometry with lanthanide-doped heavy-metal oxide in TEM March 8th, 2024

Discoveries

What heat can tell us about battery chemistry: using the Peltier effect to study lithium-ion cells March 8th, 2024

Researchers’ approach may protect quantum computers from attacks March 8th, 2024

High-tech 'paint' could spare patients repeated surgeries March 8th, 2024

Nanoscale CL thermometry with lanthanide-doped heavy-metal oxide in TEM March 8th, 2024

Announcements

What heat can tell us about battery chemistry: using the Peltier effect to study lithium-ion cells March 8th, 2024

Curcumin nanoemulsion is tested for treatment of intestinal inflammation: A formulation developed by Brazilian researchers proved effective in tests involving mice March 8th, 2024

The Access to Advanced Health Institute receives up to $12.7 million to develop novel nanoalum adjuvant formulation for better protection against tuberculosis and pandemic influenza March 8th, 2024

Nanoscale CL thermometry with lanthanide-doped heavy-metal oxide in TEM March 8th, 2024

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers/Posters

Researchers develop artificial building blocks of life March 8th, 2024

How surface roughness influences the adhesion of soft materials: Research team discovers universal mechanism that leads to adhesion hysteresis in soft materials March 8th, 2024

Curcumin nanoemulsion is tested for treatment of intestinal inflammation: A formulation developed by Brazilian researchers proved effective in tests involving mice March 8th, 2024

Nanoscale CL thermometry with lanthanide-doped heavy-metal oxide in TEM March 8th, 2024

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project