VIDEOS 1 TO 50

Particle in Infinite Potential Well (Rigid Box)

Published: 2014/03/02

Channel: AK LECTURES

Infinite square well (particle in a box)

Published: 2013/05/14

Channel: Brant Carlson

Wave Function of Particle in Finite Potential Well

Published: 2014/03/05

Channel: AK LECTURES

Lecture - 40 Potential Well

Published: 2009/01/22

Channel: nptelhrd

Lesson 19-20, Finite Square Well (updated)

Published: 2012/10/06

Channel: Steve Spicklemire

What is gravitational potential (well)?

Published: 2016/07/12

Channel: xmphysics

quantum mechanics: infinite square well (part I)

Published: 2009/09/01

Channel: jrgoldma

Quantum Well 9 : Finite Potential Well

Published: 2011/10/03

Channel: Adam Beatty

Quantum Well 1 : Infinite Potential Well (Centered at Origin)

Published: 2011/09/26

Channel: Adam Beatty

One dimensional potential well energy eigen values and normalized eigen functions

Published: 2014/12/30

Channel: Physics Reporter

21.finite.square.well

Published: 2012/10/25

Channel: utexascnsquest

PHYS3740 Lecture26-8 Finite Potential Well

Published: 2010/10/31

Channel: jmgerton

ME564 Lecture 10: Examples of nonlinear systems: particle in a potential well

Published: 2016/04/26

Channel: Steve Brunton

Particle in Finite Potential Well

Published: 2014/03/05

Channel: AK LECTURES

Mod-01 Lec-25 One-Dimensional Square Well Potential: The Bound State Problem

Published: 2013/03/04

Channel: nptelhrd

Quantum mechanical tunneling and reflection simulation

Published: 2010/02/08

Channel: Aamir Ahmed Khan

PHYS3740 Lecture26-1 Finite Potential Well

Published: 2010/10/31

Channel: jmgerton

Finite square well bound states

Published: 2013/05/14

Channel: Brant Carlson

Mod-01 Lec-26 The Square Well and the Square Potential Barrier

Published: 2013/03/04

Channel: nptelhrd

Quantum bound state(s) in a delta function potential

Published: 2013/03/26

Channel: Steuard Jensen

Quantum Well 5 : Infinite Potential Well -a/2 to a/2

Published: 2011/09/26

Channel: Adam Beatty

Lecture - 42 Potential Well

Published: 2009/01/22

Channel: nptelhrd

Lecture - 41 Potential Well

Published: 2009/01/22

Channel: nptelhrd

Potential Energy vs. Internuclear Distance (Animated) : Dr. Amal K Kumar

Published: 2013/11/09

Channel: Dr.Amal K Kumar

The bound state solution to the delta function potential TISE

Published: 2013/05/14

Channel: Brant Carlson

PHYS3740 Lecture24-1 Infinite Square Well

Published: 2010/10/26

Channel: jmgerton

The Wavefunction - Solving the Infinite Square Well Potential

Published: 2015/10/26

Channel: Tristan Kleyn

Quantum Well 2 : Infinite potential well 0 to a

Published: 2011/09/26

Channel: Adam Beatty

Particle in a Box - Infinite Potential Well

Published: 2011/03/24

Channel: David Foster

Finite square well scattering states

Published: 2013/05/14

Channel: Brant Carlson

Particle in 1-dimensional infinite potential well (part 1)

Published: 2015/06/03

Channel: MBPhysics

Quantum Well 6: Infinite Potential Well -3a to 3a

Published: 2011/09/26

Channel: Adam Beatty

Quantum Mechanics (3) 2D Infinite Potential Well - Part 1

Published: 2014/09/20

Channel: Josh Pilipovsky

11. Dispersion of the Gaussian and the Finite Well

Published: 2014/06/18

Channel: MIT OpenCourseWare

Quantum Well 3 : Infinite Potential Well 0 to 2a

Published: 2011/09/26

Channel: Adam Beatty

Finite Potential Well Example

Published: 2014/03/06

Channel: AK LECTURES

Particle Moving Above Finite Potential Well

Published: 2014/03/06

Channel: AK LECTURES

12. The Dirac Well and Scattering off the Finite Step

Published: 2014/06/18

Channel: MIT OpenCourseWare

MP25 PARTICLE SCATTERING OF A POTENTIAL WELL

Published: 2014/06/11

Channel: Shazmeen Shamsuddin

Quantum Particles in an Infinite Square Potential Well

Published: 2009/07/12

Channel: wolframmathematica

Simulation of a quantum wire - Parabolic potential well

Published: 2009/11/08

Channel: probabilityfilter

Wave packet in a potential well

Published: 2013/04/10

Channel: Wouter Hordijk

Finite Square Well Bound States Part 1

Published: 2017/02/24

Channel: Dr. Underwood's Physics YouTube Page

Purdue PHYS 342 L2.6: Schrödinger Equation in 1D: The Finite Square Well

Published: 2014/09/02

Channel: nanohubtechtalks

Particle In an Infinite Potential Well (The Energy)

Published: 2015/05/11

Channel: Everinus

Visualizing Simple Harmonic Oscillators and the Double Well Potential

Published: 2014/12/12

Channel: Jake LaNasa

Quantum Mechanics - Infinite square potential well.

Published: 2013/12/28

Channel: QuantumOverlord

Infinite Potential Well Problem

Published: 2016/11/21

Channel: Chhavi Pareek

25. Normalizing The Finite Square Well | Learn Quantum Physics

Published: 2015/04/20

Channel: Salah Salah

Purdue PHYS 342 L2.5: Schrödinger Equation in 1D: 1D Infinite Square Well

Published: 2014/09/02

Channel: nanohubtechtalks

From Wikipedia, the free encyclopedia

A **potential well** is the region surrounding a local minimum of potential energy. Energy captured in a potential well is unable to convert to another type of energy (kinetic energy in the case of a gravitational potential well) because it is captured in the local minimum of a potential well. Therefore, a body may not proceed to the global minimum of potential energy, as it would naturally tend to due to entropy.

Energy may be released from a potential well if sufficient energy is added to the system such that the local maximum is surmounted. In quantum physics, potential energy may escape a potential well without added energy due to the probabilistic characteristics of quantum particles; in these cases a particle may be imagined to tunnel *through* the walls of a potential well.

The graph of a 2D potential energy function is a potential energy surface that can be imagined as the Earth's surface in a landscape of hills and valleys. Then a potential well would be a valley surrounded on all sides with higher terrain, which thus could be filled with water (e.g., be a lake) without any water flowing away toward another, lower minimum (e.g. sea level).

In the case of gravity, the region around a mass is a gravitational potential well, unless the density of the mass is so low that tidal forces from other masses are greater than the gravity of the body itself.

A potential hill is the opposite of a potential well, and is the region surrounding a local maximum.

**Quantum confinement** can be observed once the diameter of a material is of the same magnitude as the de Broglie wavelength of the electron wave function.^{[1]} When materials are this small, their electronic and optical properties deviate substantially from those of bulk materials.^{[2]}

A particle behaves as if it were free when the confining dimension is large compared to the wavelength of the particle. During this state, the bandgap remains at its original energy due to a continuous energy state. However, as the confining dimension decreases and reaches a certain limit, typically in nanoscale, the energy spectrum becomes discrete. As a result, the bandgap becomes size-dependent. This ultimately results in a blueshift in light emission as the size of the particles decreases.

Specifically, the effect describes the phenomenon resulting from electrons and electron holes being squeezed into a dimension that approaches a critical quantum measurement, called the exciton Bohr radius. In current application, a quantum dot such as a small sphere confines in three dimensions, a quantum wire confines in two dimensions, and a quantum well confines only in one dimension. These are also known as zero-, one- and two-dimensional potential wells, respectively. In these cases they refer to the number of dimensions in which a confined particle can act as a free carrier. See external links, below, for application examples in biotechnology and solar cell technology.

See also: Particle in a box

Τhe electronic and optical properties of materials are affected by size and shape. Well-established technical achievements including quantum dots were derived from size manipulation and investigation for their theoretical corroboration on quantum confinement effect.^{[3]} The major part of the theory is the behaviour of the exciton resembles that of an atom as its surrounding space shortens. A rather good approximation of an exciton’s behaviour is the 3-D model of a particle in a box.^{[4]} The solution of this problem provides a sole^{[clarification needed]} mathematical connection between energy states and the dimension of space. Decreasing the volume or the dimensions of the available space, increases the energy of the states. Shown in the diagram is the change in electron energy level and bandgap between nanomaterial and its bulk state.

The following equation shows the relationship between energy level and dimension spacing:

Research results^{[5]} provide an alternative explanation of the shift of properties at nanoscale. In the bulk phase, the surfaces appear to control some of the macroscopically observed properties. However, in nanoparticles, surface molecules do not obey the expected configuration^{[which?]} in space. As a result, surface tension changes tremendously.

The Young-Laplace equation can give a background on the investigation of the scale of forces applied to the surface molecules:

Under the assumption of spherical shape R1=R2=R and resolving the Young-Laplace equation for the new radii R(nm), we estimate the new ΔP(GPa). The smaller the R, the greater the pressure is present. The increase in pressure at the nanoscale results in strong forces toward the interior of the particle. Consequently, the molecular structure of the particle appears to be different from the bulk mode, especially at the surface. These abnormalities at the surface are responsible for changes of inter-atomic interactions and bandgap.^{[6]}^{[7]}

**^**M. Cahay (2001).*Quantum Confinement VI: Nanostructured Materials and Devices : Proceedings of the International Symposium*. The Electrochemical Society. ISBN 978-1-56677-352-2. Retrieved 19 June 2012.**^**Hartmut Haug; Stephan W. Koch (1994).*Quantum Theory of the Optical and Electronic Properties of Semiconductors*. World Scientific. ISBN 978-981-02-2002-0. Retrieved 19 June 2012.**^**Norris, DJ; Bawendi, MG (1996). "Measurement and assignment of the size-dependent optical spectrum in CdSe quantum dots".*Physical Review B*.**53**(24): 16338–16346. Bibcode:1996PhRvB..5316338N. doi:10.1103/PhysRevB.53.16338. PMID 9983472.**^**Brus, L. E. (1983). "A simple model for the ionization potential, electron affinity, and aqueous redox potentials of small semiconductor crystallites".*The Journal of Chemical Physics*.**79**(11): 5566. Bibcode:1983JChPh..79.5566B. doi:10.1063/1.445676.**^**Kunz, A B; Weidman, R S; Collins, T C (1981). "Pressure-induced modifications of the energy band structure of crystalline CdS".*Journal of Physics C: Solid State Physics*.**14**(20): L581. Bibcode:1981JPhC...14L.581K. doi:10.1088/0022-3719/14/20/004.**^**H. Kurisu; T. Tanaka; T. Karasawa; T. Komatsu (1993). "Pressure induced quantum confined excitons in layered metal triiodide crystals".*Jpn. J. Appl. Phys*.**32**(Supplement 32–1): 285–287. Bibcode:1993JJAPS..32..285K. doi:10.7567/jjaps.32s1.285.**^**Lee, Chieh-Ju; Mizel, Ari; Banin, Uri; Cohen, Marvin L.; Alivisatos, A. Paul (2000). "Observation of pressure-induced direct-to-indirect band gap transition in InP nanocrystals".*The Journal of Chemical Physics*.**113**(5): 2016. Bibcode:2000JChPh.113.2016L. doi:10.1063/1.482008.

- Buhro WE, Colvin VL (2003). "Semiconductor nanocrystals: Shape matters".
*Nat Mater*.**2**(3): 138–9. Bibcode:2003NatMa...2..138B. doi:10.1038/nmat844. PMID 12612665. - Semiconductor Fundamental
- Band Theory of Solid
- Quantum dots synthesis
- Biological application

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