Unit 7 Study Notes: Particle Physics & Solid State Applications

The Standard Model

A theoretical framework describing the fundamental building blocks of the universe and the forces through which they interact.

Strong Nuclear Force

The strongest fundamental force, acting on quarks and hadrons, with a relative strength of 1.

Electromagnetism

A fundamental force acting on electrically charged particles, with a relative strength of 10^-2 and infinite range.

Weak Nuclear Force

A fundamental force acting on quarks and leptons, with a relative strength of 10^-6 and a short range.

Gravity

The weakest fundamental force, with a relative strength of 10^-39 and infinite range.

Quarks

Fundamental constituents of matter that never exist in isolation due to color confinement.

Hadrons

Composite particles made of quarks, including baryons and mesons.

Baryons

Hadrons made of three quarks, like protons and neutrons.

Mesons

Hadrons made of a quark and an antiquark.

Leptons

Fundamental particles that do not interact via the Strong Force and can exist freely.

Neutrinos

Leptons with tiny mass and no electric charge that interact very weakly with matter.

Antimatter

Particles that have the same mass but opposite charge of their corresponding matter particles.

Conservation of Charge

The principle that the total net charge before and after a reaction must be equal.

Conservation of Baryon Number

The principle that the sum of baryon numbers must be conserved in any reaction.

Conservation of Lepton Number

The principle that the total lepton number before and after a reaction must be equal.

Doping

The process of adding impurities to silicon to change its electrical properties.

N-Type Semiconductor

Silicon doped with elements providing extra electrons, making electrons the majority carriers.

P-Type Semiconductor

Silicon doped with elements creating holes, making these holes the majority charge carriers.

P-N Junction

The boundary formed when P-type and N-type materials are joined, creating an internal electric field.

LED (Light Emitting Diode)

A device that emits light when current flows through a P-N junction, as electrons drop into holes.

Photovoltaic Cell

A device that converts light energy into electrical energy through the excitation of electrons.

Band Theory

A theory that explains the behavior of electrons in solids and the formation of energy bands.

Energy Band Gap (Eg)

The energy difference between the valence band and conduction band in solids; no electrons can exist here.

Fermions

Matter particles, such as quarks and leptons, that obey the Pauli exclusion principle.

Bosons

Force carrier particles that mediate fundamental forces, such as gluons and photons.

Color Confinement

The phenomenon where quarks are never found in isolation but are always bound within hadrons.

Depletion Region

A non-conductive zone created at the P-N junction where electrons fill holes.