The Quantum Afterburner

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The Quantum Afterburner
http//www.physicsweb.org/article/news/6/2/2
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The Article In Few Words
We here show that it is indeed possible to
improve on the efficiency of an ideal Otto cycle
engine, operating between two fixed temperature
reservoirs, by adding a quantum afterburner which
extracts coherent laser energy from the Internal
degrees of freedom of the hot exhaust gases of
the heat engine.
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Presentation Contents

• The Otto Engine
• The Quantum Otto Engine (QOE)
• Lasers
• Atomic levels in QOE
• Efficiency
• Conclusions

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The Otto Engine

• Isoentropic expansion
• Isochoric cooling
• Isobaric exhaustion
• Isobaric intake
• Isoentropic compression
• Isochoric heating

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The simplified Otto Engine

• Isoentropic expansion
• Isochoric cooling
• Isobaric exhaustion
• Isobaric intake
• Isoentropic compression
• Isochoric heating

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5
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The Quantum Otto Engine (1)
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The Quantum Otto Engine (2)


8
Laser
Laser Pump
Light Amplification by Stimulated Emission of
Radiation
State 2
Laser transition
State 1
Fast Decay
Ground State
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Atomic Levels in QOE

• The maser cavity establishes a thermal
  distribution of population between b? and c?
  determined by T3
• After the maser population inversion between a?
  and b?
• Atomic states are long lived when not in the
  cavity

a?
b?
c?
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Efficiency of the QOE
Otto Engine
Quantum Otto Engine
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Conclusions

• The QOE binds together thermodinamics and recent
  developments in quantum optics
• In principle it works
• The efficiency of the QOE is improved
• Quantum afterburning does not apply to Carnot
  cycles
• 6/11 quotations refers to the author of this
  article