Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Atomic Nuclei: Nuclear Spin State Population Distribution

Atomic Nuclei: Nuclear Spin State Population Distribution

Near absolute zero temperatures, in the presence of a magnetic field, the majority of nuclei prefer the lower energy spin-up state to the higher energy spin-down state. As temperatures increase, the energy from thermal collisions distributes the spins more equally between the two states. The Boltzmann distribution equation gives the ratio of the number of spins predicted in the spin −½ (N−) and spin +½ (N+) states.

Atomic Nuclei: Nuclear Relaxation Processes

Atomic Nuclei: Nuclear Relaxation Processes

In the absence of an external magnetic field, nuclear spin states are degenerate and randomly oriented. When a magnetic field is applied, the spins begin to precess and orient themselves along (lower energy) or against (higher energy) the direction of the field. At equilibrium, a slight excess population of spins exists in the lower energy state. Because the direction of the magnetic field is fixed as the z-axis, the precessing magnetic moments are randomly oriented around the z-axis. This...

Atomic Nuclei: Nuclear Spin State Overview

Atomic Nuclei: Nuclear Spin State Overview

NMR-active nuclei have energy levels called 'spin states' that are associated with the orientations of their nuclear magnetic moments. In the absence of a magnetic field, the nuclear magnetic moments are randomly oriented, and the spin states are degenerate. When an external magnetic field is applied, the spin states have only 2 + 1 orientations available to them. A proton with = ½ has two available orientations. Similarly, for a quadrupolar nucleus with a nuclear spin value of one, the...

NMR Spectroscopy: Spin–Spin Coupling

NMR Spectroscopy: Spin–Spin Coupling

The spin state of an NMR-active nucleus can have a slight effect on its immediate electronic environment. This effect propagates through the intervening bonds and affects the electronic environments of NMR-active nuclei up to three bonds away; occasionally, even farther. This phenomenon is called spin–spin coupling or J-coupling. Coupling interactions are mutual and result in small changes in the absorption frequencies of both nuclei involved. While nuclei of the same element are involved in...

Atomic Nuclei: Types of Nuclear Relaxation

Atomic Nuclei: Types of Nuclear Relaxation

Nuclear relaxation restores the equilibrium population imbalance and can occur via spin–lattice or spin–spin mechanisms, which are first-order exponential decay processes.
In spin–lattice or longitudinal relaxation, the excited spins exchange energy with the surrounding lattice as they return to the lower energy level. Among several mechanisms that contribute to spin–lattice relaxation, magnetic dipolar interactions are significant. Here, the excited nucleus transfers energy to a nearby...

¹H NMR: Interpreting Distorted and Overlapping Signals

¹H NMR: Interpreting Distorted and Overlapping Signals

Spin systems where the difference in chemical shifts of the coupled nuclei is greater than ten times J are called first-order spin systems. These nuclei are weakly coupled, and their chemical shifts and coupling constant can generally be estimated from the well-separated signals in the spectrum.
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are slanted or...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

ΔTnoise as a robust diagnostic for chiral, helical and trivial edge modes.

Journal of physics. Condensed matter : an Institute of Physics journal·2026

Same author

ΔTnoise in mesoscopic hybrid junctions: influence of barrier strength and thermal bias.

Journal of physics. Condensed matter : an Institute of Physics journal·2025

Same author

Honing in on a topological zero-bias conductance peak.

Journal of physics. Condensed matter : an Institute of Physics journal·2023

Same author

Switching global correlations on and off in a many-body quantum state by tuning local entanglement.

Chaos (Woodbury, N.Y.)·2023

Same author

Vaccination dilemma in the thermodynamic limit.

Chaos (Woodbury, N.Y.)·2023

Same author

Josephson quantum spin thermodynamics.

Journal of physics. Condensed matter : an Institute of Physics journal·2022

Search research articles

Related Experiment Video

Updated: May 14, 2026

In Situ Monitoring of Diffusion of Guest Molecules in Porous Media Using Electron Paramagnetic Resonance Imaging

In Situ Monitoring of Diffusion of Guest Molecules in Porous Media Using Electron Paramagnetic Resonance Imaging

Published on: September 2, 2016

Negative spinΔTnoise induced by spin-flip scattering and Andreev reflection.

Sachiraj Mishra^1,2, Colin Benjamin^1,2

¹School of Physical Sciences, National Institute of Science Education and Research, HBNI, Jatni 752050, India.

Journal of Physics. Condensed Matter : an Institute of Physics Journal

|May 12, 2026

Summary

Spin noise in superconducting junctions can become negative, unlike charge noise. This sign reversal reveals unique spin-dependent scattering mechanisms, distinguishing it from quantum shot noise.

Keywords:

Andreev reflection delta-T noise mesoscopic junctions quantum noise spin-flip scattering

More Related Videos

Study of Protein Dynamics via Neutron Spin Echo Spectroscopy

Study of Protein Dynamics via Neutron Spin Echo Spectroscopy

Published on: April 13, 2022

Spin Saturation Transfer Difference NMR (SSTD NMR): A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes

Spin Saturation Transfer Difference NMR (SSTD NMR): A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes

Published on: November 12, 2016

Related Experiment Videos

Last Updated: May 14, 2026

In Situ Monitoring of Diffusion of Guest Molecules in Porous Media Using Electron Paramagnetic Resonance Imaging

In Situ Monitoring of Diffusion of Guest Molecules in Porous Media Using Electron Paramagnetic Resonance Imaging

Published on: September 2, 2016

Study of Protein Dynamics via Neutron Spin Echo Spectroscopy

Study of Protein Dynamics via Neutron Spin Echo Spectroscopy

Published on: April 13, 2022

Spin Saturation Transfer Difference NMR (SSTD NMR): A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes

Spin Saturation Transfer Difference NMR (SSTD NMR): A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes

Published on: November 12, 2016

Area of Science:

Condensed Matter Physics
Quantum Phenomena
Spintronics

Background:

Understanding noise in electronic transport is crucial for quantum device development.
Superconducting hybrid junctions offer a platform to study complex quantum correlations.

Purpose of the Study:

To investigate charge and spin noise in normal metal-spin flipper-normal metal-insulator-superconductor (N-sf-N-I-S) junctions.
To analyze the conditions leading to sign reversal in spin noise and its implications.

Main Methods:

Theoretical analysis of charge and spin noise in N-sf-N-I-S junctions.
Examination of the interplay between spin-flip scattering and Andreev reflection.

Main Results:

Charge noise is always positive, while spin noise can reverse sign from positive to negative.
Negative spin noise arises from opposite-spin correlations, distinct from same-spin correlations in quantum shot noise.
This sign reversal provides insights into scattering mechanisms not detectable by quantum shot noise alone.

Conclusions:

Negative spin noise acts as a unique probe for cooperative effects of Andreev reflection and spin flipping.
The findings highlight the role of spin-dependent scattering in superconducting hybrid devices.
This work offers new perspectives on noise mechanisms and their fingerprints in quantum systems.