herb kroemer optical patents: the alpha and the omega…
DESCRIPTION
Herb Kroemer Optical Patents: The alpha and the omega…. Kroemer Symposium John Bowers May 20 , 2013. Herb’s First Optical Patent: Double Heterostructure Laser. Filed: 1963 Issued: 1967 Expired: 1985. Patent 3,309,553. - PowerPoint PPT PresentationTRANSCRIPT
Herb Kroemer Optical Patents:The alpha and the omega…
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Kroemer SymposiumJohn BowersMay 20, 2013
Herb’s First Optical Patent: Double Heterostructure Laser
Filed: 1963Issued: 1967Expired: 1985
Patent 3,309,553
Double Heterostructure Laser Diode: The first cw semiconductor laser
Izuo Hayashi (left) and Morton Panish (1971) at Bell Labs were able to design the first semiconductor laser that operated continuously at room temperature. The need for semiconductor heterostructures for efficient laser diode operation was put forward by Herbert Kroemer. (Reprinted with permission of Alcatel–Lucent USA Inc.)
M. B. Panish et al. APL 16(8), 1970
400x
0 0.4 0.8 1.2 1.60
5E+017
1E+018
1.5E+018
2E+018
Distance from surface (mm)El
ectro
n C
once
ntra
tion
(cm
-2)
Carrier confinement
Heterojunction Homojunction
Higher optical losses
0 0.4 0.8 1.2 1.60
5E+017
1E+018
1.5E+018
2E+018
Distance from surface (mm)
Elec
tron
Con
cent
ratio
n (c
m-2
)
Heterojunction Homojunction
Index profile
Intensity profile
1%
10%
1 exp Cd n n : the difference in the reflective indexd : the thickness of the active layer, C : Constant
Optical confinement
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How Important is this Invention?
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How Important is this Invention?
About $4B annually
Laser Focus World Jan. 2013
All commercial diode lasers use double heterostructures
Herb’s patent runs out
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Herb’s second optical patent
Light-emitting structures in silicon are more attractive from a fabrication standpoint…light generation in silicon is an inefficient process…
Herb’s Latest Optical Patent: Optical Isolator
Hybrid Silicon Ring Isolator
1551.0 1551.1 1551.2 1551.3 1551.4-60
-58
-56
-54
-52
-50
-48
-46
Tran
smis
sion
(dB
m)
Wavelength (nm)
inward-direction magnetic field outward-direction magnetic field
Tien et al. “Silicon ring isolators with bonded nonreciprocal magneto-optic garnet” Optics Express (2011).
First experiment Optimized design
Herb: Thank you!
• For your insights• For setting high standards in research, and faculty
and students recruiting• For tolerating my research on hybrid III-V silicon
photonics…the gain is in the III-V after all, not like those MIT guys…and you were 45 years ahead anyway.
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