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MICHELSON MORLEY EXPERIMENT

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MEISNER EFFECT ON SUPERCONDUCTORS

Meissner effect.

UNIT CELL AND LATTICE PARAMETERS

Unit cell In Crystals the arrangement of particles is described with three dimensional geometrical  parallelepiped structure.  The unit cell is defined as the smallest size of parallelepiped structure with  minimum number of atoms. In a unit cell there are 6 faces and 8 corners. So 8 atoms are required to form a unit cell and all the  8 atoms are located at the 8 corners each. Lattice Lattice is defined as a three dimensional array of atoms. It describes the size and shape of the unit cell. Parameters of a unit cell A unit cell is described by six parameters. These parameters are three dimensions  and the  angles between them . The Dimensions of unit cell  along three axes of a unit cell are represented by (a, b ,c) . The angle between b and c is represented by α, between a and c by β and between a and b by γ. we can identify the structure of crystal by knowing the parameters of unit cell. Properties of unit cell : 1. Unit cell is...

MILLER INDICES - SIGNIFICANCE

Crystal planes : Crystal planes are defined as imaginary planes inside a crystal lattice passing through the atoms  along x, y and Z directions.  These planes are represented as XY, YZ, ZX and XYZ planes. We cannot  find a single plane in a crystal lattice but set of parallel planes are observed. Miller indices: Miller indices are defined as the reciprocals of intercepts of crystal plane. They are used to  represent the direction of crystal planes. Miller indices are denoted as the coordinates ( h, k, l ) . h : k : l = 1/p : 1/q : 1/r Miller indices represent the structure of unit cell. Procedure to find Miller indices: 1. Identify the plane intercepts on the x, y and z-axes. 2. Represent intercepts in fractional coordinates as ( p, q, r) 3. Take the reciprocals of the fractional intercepts h : k : l = 1/p : 1/q : 1/r 4. convert the small fractions into integers by multiplying with their least common factor  LCM. Significance ...