Solid state radiative heat pump

Patent · Wed Jan 01 00:00:00 EST 1986

OSTI ID:866079

Berdahl, Paul H ^[1]

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1. Oakland, CA

A solid state radiative heat pump (10, 50, 70) operable at room temperature (300.degree. K.) utilizes a semiconductor having a gap energy in the range of 0.03-0.25 eV and operated reversibly to produce an excess or deficit of charge carriers as compared to thermal equilibrium. In one form of the invention (10, 70) an infrared semiconductor photodiode (21, 71) is used, with forward or reverse bias, to emit an excess or deficit of infrared radiation. In another form of the invention (50), a homogeneous semiconductor (51) is subjected to orthogonal magnetic and electric fields to emit an excess or deficit of infrared radiation. Three methods of enhancing transmission of radiation through the active surface of the semiconductor are disclosed. In one method, an anti-reflection layer (19) is coated into the active surface (13) of the semiconductor (11), the anti-reflection layer (19) having an index of refraction equal to the square root of that of the semiconductor (11). In the second method, a passive layer (75) is spaced from the active surface (73) of the semiconductor (71) by a submicron vacuum gap, the passive layer having an index of refractive equal to that of the semiconductor. In the third method, a coupler (91) with a paraboloid reflecting surface (92) is in contact with the active surface (13, 53) of the semiconductor (11, 51), the coupler having an index of refraction about the same as that of the semiconductor.

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• DOE Contract Number: AC03-76SF00098
• Assignee: United States of America as represented by United States (Washington, DC)
• Patent Number(s): US 4628695
• OSTI ID: 866079
• Country of Publication: United States
• Language: English

Related Subjects

solid
radiative
heat
pump
10
50
70
operable
temperature
300
degree
utilizes
semiconductor
gap
energy
range
03-0
25
operated
reversibly
produce
excess
deficit
charge
carriers
compared
thermal
equilibrium
form
infrared
photodiode
21
71
forward
reverse
bias
emit
radiation
homogeneous
51
subjected
orthogonal
magnetic
electric
fields
methods
enhancing
transmission
active
surface
disclosed
method
anti-reflection
layer
19
coated
13
11
index
refraction
equal
square
root
passive
75
spaced
73
submicron
vacuum
refractive
third
coupler
91
paraboloid
reflecting
92
contact
53
radiative heat
charge carrier
gap energy
charge carriers
heat pump
electric field
infrared radiation
reflecting surface
active surface
electric fields
thermal equilibrium
third method
reverse bias
/62/