Related Experiment Video
Updated: Nov 5, 2025
06:51
Microparticle Manipulation by Standing Surface Acoustic Waves with Dual-frequency Excitations
Published on: August 21, 2018
7.2K
Near Field Propulsion Forces from Nonreciprocal Media
David Gelbwaser-Klimovsky1, Noah Graham2, Mehran Kardar3
1Physics of Living Systems, Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Physical Review Letters
|May 14, 2021
Summary
A novel Casimir force engine requires nonreciprocal materials for operation. This setup converts heat radiation into mechanical force, with efficiency limited by Carnot value.
Area of Science:
- Thermodynamics
- Condensed Matter Physics
- Nanotechnology
Background:
- Casimir forces typically arise from quantum fluctuations.
- Previous models suggested symmetry and thermodynamics could enable a lateral Casimir force.
- Broken inversion symmetry is a key factor in Casimir force phenomena.
Purpose of the Study:
- To investigate the conditions necessary for a ratchetlike lateral Casimir force.
- To determine if such a force can operate as a heat engine.
- To analyze the efficiency and operational velocity of this proposed engine.
Main Methods:
- Theoretical analysis of Casimir forces between plates at different temperatures.
- Inclusion of nonreciprocal material properties in the theoretical model.
- Extension of Onsager symmetry principles to nonreciprocal systems.
Main Results:
- A lateral Casimir force requires at least one nonreciprocal material plate.
- The setup functions as a heat engine, converting thermal radiation to mechanical force.
- Engine efficiency is limited to the Carnot value, even with nonreciprocal materials.
Conclusions:
- Nonreciprocal materials are essential for realizing a lateral Casimir force heat engine.
- The theoretical framework extends Onsager symmetry to nonreciprocal systems.
- Optimal operating velocities are dependent on material properties and distance, approaching the speed of light.
Related Concept Videos
01:09Types of Forces
12.9K
In most situations, forces can be grouped into two categories: contact forces and field forces. Contact forces occur as a result of direct physical contact between objects. Field forces, however, act without the necessity of physical contact between objects. They depend on the presence of a "field" in the region of space surrounding the body under consideration. You can think of a field as a property of space that is detectable by the forces it exerts. Scientists think there...
12.9K
01:07Propagation of Waves
2.6K
When a wave propagates from one medium to another, part of it may get reflected in the first medium, and part of it may get transmitted to the second medium. In such a case, the interface of the two mediums can be considered as a boundary that is neither fixed nor free.
Consider a scenario where a wave propagates from a string of low linear mass density to a string of high linear mass density. In such a case, the reflected wave is out of phase with respect to the incident wave, however the...
Consider a scenario where a wave propagates from a string of low linear mass density to a string of high linear mass density. In such a case, the reflected wave is out of phase with respect to the incident wave, however the...
2.6K
01:25Introduction to force
863
Consider water flowing from a nozzle to a turbine vane. As the water hits the turbine vane, it exerts a force that causes it to move along the flow of direction. Force is an impact that changes an object's motion, shape, or orientation. Forces can be caused by physical contact, such as a push or pull, or through non-contact interactions, such as magnetic or gravitational forces. Force is a vector quantity with both magnitude and direction, and is measured in newtons (N) in the SI unit...
863
01:22Force Classification
1.9K
Forces play a crucial role in the study of physics and engineering. They are essential in describing the motion, behavior, and equilibrium of objects in the physical world. Forces can be classified based on their origin, type, and direction of action.
Contact and non-contact forces are two of the most widely used categories of forces. As the name suggests, contact forces require physical contact between two objects to act upon each other. Examples of contact forces include frictional,...
Contact and non-contact forces are two of the most widely used categories of forces. As the name suggests, contact forces require physical contact between two objects to act upon each other. Examples of contact forces include frictional,...
1.9K
01:20Rocket Propulsion in Gravitational Field - I
3.0K
Rockets range in size from small fireworks that ordinary people use to the enormous Saturn V that once propelled massive payloads toward the Moon. The propulsion of all rockets, jet engines, deflating balloons, and even squids and octopuses are explained by the same physical principle: Newton's third law of motion. The matter is forcefully ejected from a system, producing an equal and opposite reaction on what remains.
The motion of a rocket in space changes its velocity (and hence its...
The motion of a rocket in space changes its velocity (and hence its...
3.0K
01:27Non-inertial Frames of Reference
6.6K
A reference frame accelerating or decelerating relative to an inertial frame is a non-inertial frame. To help understand this, consider what taking off in an airplane, turning a corner in a car, riding a merry-go-round, and the circular motion of a tropical cyclone all have in common. All these systems are accelerating, decelerating, or rotating relative to the Earth; hence, they all are non-inertial frames. All these systems exhibit inertial forces, which merely seem to arise from motion,...
6.6K