Surface-barrier reflection of diffusing positrons

Journal Article · Wed May 01 00:00:00 EDT 1991 · Physical Review, B: Condensed Matter; (USA)

DOI:https://doi.org/10.1103/PhysRevB.43.10111· OSTI ID:5795001

Brandes, G R ^[1]

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1. Department of Physics, Brandeis University, Waltham, Massachusetts 02254 (US)

The reemitted positron yield from a 1500-A-thick Ni(100) foil was measured as a function of incident positron energy. The magnitude of the positron internal surface reflection coefficient, {ital scrR}=0.63{plus minus}0.04, was determined by fitting calculated positron yields to the data. This value agrees with the value calculated using the one-dimensional, potential-step model advanced by Britton {ital et} {ital al}. (Phys. Rev. Lett. 62, 2413 (1989)). The mean positron penetration depth varies with incident positron energy as {ital {bar z}}={alpha}{ital E}{sup {ital n}}, where {alpha} is fixed ({alpha}=400/{rho} A/keV{sup {ital n}}, {rho} is the sample density in g cm{sup {minus}3}) and {ital n}=1.61{plus minus}0.03, in good agreement with positron back-reemission measurements from thick single crystals.

• OSTI ID: 5795001
• Journal Information: Physical Review, B: Condensed Matter; (USA), Journal Name: Physical Review, B: Condensed Matter; (USA) Vol. 43:13; ISSN PRBMD; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

656003* -- Condensed Matter Physics-- Interactions between Beams & Condensed Matter-- (1987-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ANTILEPTONS
ANTIMATTER
ANTIPARTICLES
COLLISIONS
DIFFUSION
ELEMENTARY PARTICLES
ELEMENTS
ENERGY RANGE
FERMIONS
FILMS
FOILS
KEV RANGE
LEPTONS
METALS
NICKEL
POSITRON COLLISIONS
POSITRONS
POTENTIALS
SLOWING-DOWN
SURFACE POTENTIAL
THERMALIZATION
THIN FILMS
TRANSITION ELEMENTS
TRANSMISSION