Modal study of refractive effects on x-ray laser coherence

Conference · Mon Dec 09 04:00:00 EST 1991

OSTI ID:5705392

Amendt, P; London, R A ^[1]; Strauss, M ^[2]

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1. Lawrence Livermore National Lab., CA (United States)
2. Israel Atomic Energy Commission, Beersheba (Israel). Nuclear Research Center-Negev

The role of smoothly varying transverse gain and refraction profiles on x-ray laser coherence is analyzed by modally expanding the laser electric field within the paraxial approximation. Comparison with a square transverse profile reveals that smoothly varying profiles generally lead to a greatly reduced number of guided modes and a consequent improvement in transverse coherence length. However, the refractive defocussing responsible for enhanced coherence can also significantly degrade the coherent power of x-ray lasers based on amplified spontaneous emission. An optimal value to Fresnel number is indicated, below which the coherent power rapidly decreases as refractive defocussing is increased. Further improvement in the coherence length without degradation of coherent power may require multipass architectures with spatial filtering instead of relying on increased refraction through narrowing of the laser. 13 refs.

• Research Organization: Lawrence Livermore National Lab., CA (United States)
• Sponsoring Organization: DOE; USDOE, Washington, DC (United States)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 5705392
• Report Number(s): UCRL-JC-105736-Rev.1; CONF-9104164--3-Rev.1; ON: DE92007338
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
426002* -- Engineering-- Lasers & Masers-- (1990-)
661300 -- Other Aspects of Physical Science-- (1992-)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AMPLIFICATION
COHERENT RADIATION
ELECTROMAGNETIC RADIATION
GAIN
HOLOGRAPHY
LASER RADIATION
LASERS
MATHEMATICAL MODELS
NORMAL-MODE ANALYSIS
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
RADIATIONS
REFRACTIVITY
X-RAY LASERS