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• 1. [Article] Output Properties of Short-Pulse Gain-Switched Lasers

  A formalism is derived for analyzing the spectral and temporal properties of gain-switched lasers. The development of the longitudinal mode structure from spontaneous emission, limiting linewidths, and ...

  Citation × Citation Citation Abstract Copy Title: Output Properties of Short-Pulse Gain-Switched Lasers Author: Casperson, Lee W. Year: 1974 A formalism is derived for analyzing the spectral and temporal properties of gain-switched lasers. The development of the longitudinal mode structure from spontaneous emission, limiting linewidths, and over-all spectral characteristics are considered in detail; and applications are discussed. Title: Output Properties of Short-Pulse Gain-Switched Lasers Author: Casperson, Lee W. Year: 1974 A formalism is derived for analyzing the spectral and temporal properties of gain-switched lasers. The development of the longitudinal mode structure from spontaneous emission, limiting linewidths, and over-all spectral characteristics are considered in detail; and applications are discussed. Close

• 2. [Article] Oscillation frequency in high-gain lasers

  The calculation of the oscillation frequency of a single-mode laser oscillator is examined systematically. Mode-pulling formulas are developed for a variety of laser systems, and the limitations of a standard ...

  Citation × Citation Citation Abstract Copy Title: Oscillation frequency in high-gain lasers Author: Casperson, Lee W. Year: 1990 The calculation of the oscillation frequency of a single-mode laser oscillator is examined systematically. Mode-pulling formulas are developed for a variety of laser systems, and the limitations of a standard approximation are explored. Title: Oscillation frequency in high-gain lasers Author: Casperson, Lee W. Year: 1990 The calculation of the oscillation frequency of a single-mode laser oscillator is examined systematically. Mode-pulling formulas are developed for a variety of laser systems, and the limitations of a standard approximation are explored. Close

• 3. [Article] Pulse evolution in CO₂ lasers

  Explicit formulas are examined for the development of optical pulses in gain‐switched or Q‐switched laser oscillators and for the distortion of such pulses in succeeding stages of laser amplification. ...

  Citation × Citation Citation Abstract Copy Title: Pulse evolution in CO₂ lasers Author: Casperson, Lee W., Herbst, M. J., Turechek, John J. Year: 1976 Explicit formulas are examined for the development of optical pulses in gain‐switched or Q‐switched laser oscillators and for the distortion of such pulses in succeeding stages of laser amplification. The results are compared to data obtained with a TEA CO₂ oscillator‐amplifier system. Title: Pulse evolution in CO₂ lasers Author: Casperson, Lee W., Herbst, M. J., Turechek, John J. Year: 1976 Explicit formulas are examined for the development of optical pulses in gain‐switched or Q‐switched laser oscillators and for the distortion of such pulses in succeeding stages of laser amplification. The results are compared to data obtained with a TEA CO₂ oscillator‐amplifier system. Close

• 4. [Article] Gaussian Light Beams in Inhomogeneous Media

  Vector wave solutions are obtained for the propagation of beams of light in media having slow spatial variations of the gain, loss, or index of refraction. The formalism developed here is applicable to ...

  Citation × Citation Citation Abstract Copy Title: Gaussian Light Beams in Inhomogeneous Media Author: Casperson, Lee W. Year: 1973 Vector wave solutions are obtained for the propagation of beams of light in media having slow spatial variations of the gain, loss, or index of refraction. The formalism developed here is applicable to a wide range of problems, and an exa mple considered in detail is the propagation of off-axis beams in lenslike laser materials and optical waveguides. A procedure is also described for the diagnosis of localized dielectric inhomogeneities such as plasmas by means of Gaussian laser beams. Title: Gaussian Light Beams in Inhomogeneous Media Author: Casperson, Lee W. Year: 1973 Vector wave solutions are obtained for the propagation of beams of light in media having slow spatial variations of the gain, loss, or index of refraction. The formalism developed here is applicable to a wide range of problems, and an exa mple considered in detail is the propagation of off-axis beams in lenslike laser materials and optical waveguides. A procedure is also described for the diagnosis of localized dielectric inhomogeneities such as plasmas by means of Gaussian laser beams. Close

• 5. [Article] Rayleigh-Debye scattering with focused laser beams

  A focused beam technique has been developed for diagnosing the characteristics of individual particles within a polydisperse ensemble. In the Rayleigh-Debye approximation the scattered fields are related ...

  Citation × Citation Citation Abstract Copy Title: Rayleigh-Debye scattering with focused laser beams Author: Casperson, Lee W., Yeh, Cavour W. Year: 1978 A focused beam technique has been developed for diagnosing the characteristics of individual particles within a polydisperse ensemble. In the Rayleigh-Debye approximation the scattered fields are related to the orientation and properties of a scatterer by means of explicit analytic formulas. The results simplify when the particle size is small compared to the minimum beam diameter. Title: Rayleigh-Debye scattering with focused laser beams Author: Casperson, Lee W., Yeh, Cavour W. Year: 1978 A focused beam technique has been developed for diagnosing the characteristics of individual particles within a polydisperse ensemble. In the Rayleigh-Debye approximation the scattered fields are related to the orientation and properties of a scatterer by means of explicit analytic formulas. The results simplify when the particle size is small compared to the minimum beam diameter. Close

• 6. [Article] Field-Equation Approximations and Amplification in High-Gain Lasers: Numerical Results

  It has recently been shown that a field-equation time-derivative approximation that is commonly used in studies of laser-oscillator dynamics is not necessary and can lead to significant errors for some ...

  Citation × Citation Citation Abstract Copy Title: Field-Equation Approximations and Amplification in High-Gain Lasers: Numerical Results Author: Casperson, Lee W. Year: 1991 It has recently been shown that a field-equation time-derivative approximation that is commonly used in studies of laser-oscillator dynamics is not necessary and can lead to significant errors for some lasers. A related space-derivative approximation is widely used in studies of steady-state laser amplifiers. A more rigorous amplifier formalism is developed here, and the results are exact solutions of Maxwell’s equations. The improved model predicts a spatial instability, single mirror oscillation, and other interesting field behavior. Title: Field-Equation Approximations and Amplification in High-Gain Lasers: Numerical Results Author: Casperson, Lee W. Year: 1991 It has recently been shown that a field-equation time-derivative approximation that is commonly used in studies of laser-oscillator dynamics is not necessary and can lead to significant errors for some lasers. A related space-derivative approximation is widely used in studies of steady-state laser amplifiers. A more rigorous amplifier formalism is developed here, and the results are exact solutions of Maxwell’s equations. The improved model predicts a spatial instability, single mirror oscillation, and other interesting field behavior. Close

• 7. [Article] Plasma Diagnosis by Laser Beam Scanning

  A procedure is developed for determining the radial electron density and temperature profiles of a rotationally symmetric plasma. This high‐resolution technique involves measuring the deflection of laser ...

  Citation × Citation Citation Abstract Copy Title: Plasma Diagnosis by Laser Beam Scanning Author: Casperson, Lee W., Cheng, T. K. Year: 1975 A procedure is developed for determining the radial electron density and temperature profiles of a rotationally symmetric plasma. This high‐resolution technique involves measuring the deflection of laser beams incident transverse to the plasma. Diagnosis of a stable atmospheric pressure argon arc with CO₂ and He‐Ne laser beams yields results in good agreement with spectroscopic methods. Title: Plasma Diagnosis by Laser Beam Scanning Author: Casperson, Lee W., Cheng, T. K. Year: 1975 A procedure is developed for determining the radial electron density and temperature profiles of a rotationally symmetric plasma. This high‐resolution technique involves measuring the deflection of laser beams incident transverse to the plasma. Diagnosis of a stable atmospheric pressure argon arc with CO₂ and He‐Ne laser beams yields results in good agreement with spectroscopic methods. Close

• 8. [Article] Grazing Reflection of Gaussian Beams

  The reflectivities of most surfaces are higher for grazing or near-90-deg angles of incidence than for more perpendicular or near-zero-deg angles. Grazing-incidence configurations are especially important ...

  Citation × Citation Citation Abstract Copy Title: Grazing Reflection of Gaussian Beams Author: Casperson, Lee W. Year: 1999 The reflectivities of most surfaces are higher for grazing or near-90-deg angles of incidence than for more perpendicular or near-zero-deg angles. Grazing-incidence configurations are especially important in the development of lasers and optical systems that operate in the far-ultraviolet and soft-x-ray regions of the spectrum, where transparent or highly reflecting media are almost unknown. Analytical solutions of the paraxial wave equation are obtained for the grazing reflection and complex interference effects that take place when a Gaussian beam interacts at shallow angles with a reflecting surface. Title: Grazing Reflection of Gaussian Beams Author: Casperson, Lee W. Year: 1999 The reflectivities of most surfaces are higher for grazing or near-90-deg angles of incidence than for more perpendicular or near-zero-deg angles. Grazing-incidence configurations are especially important in the development of lasers and optical systems that operate in the far-ultraviolet and soft-x-ray regions of the spectrum, where transparent or highly reflecting media are almost unknown. Analytical solutions of the paraxial wave equation are obtained for the grazing reflection and complex interference effects that take place when a Gaussian beam interacts at shallow angles with a reflecting surface. Close

• 9. [Article] Effects of Focusing-Beam Field Variations on the Stability of Laser Oscillators

  Semiclassical models for the dynamical behavior of single-longitudinal-mode, homogeneously broadened, unidirectional ring-laser oscillators have long been available. However, in most of these models the ...

  Citation × Citation Citation Abstract Copy Title: Effects of Focusing-Beam Field Variations on the Stability of Laser Oscillators Author: Chenkosol, Pitak, Casperson, Lee W. Year: 2005 Semiclassical models for the dynamical behavior of single-longitudinal-mode, homogeneously broadened, unidirectional ring-laser oscillators have long been available. However, in most of these models the beam's cross section is assumed to be independent of longitudinal position in the laser, while in practical laser systems it is common for the diameter to vary with position. A model for lasers with focusing-beam field variations is developed here. Linear stability analysis shows that higher values of excitation are required to reach the type 1 instability threshold for lasers with longitudinal variations of the beam diameter than for the uniform plane-wave laser model. Title: Effects of Focusing-Beam Field Variations on the Stability of Laser Oscillators Author: Chenkosol, Pitak, Casperson, Lee W. Year: 2005 Semiclassical models for the dynamical behavior of single-longitudinal-mode, homogeneously broadened, unidirectional ring-laser oscillators have long been available. However, in most of these models the beam's cross section is assumed to be independent of longitudinal position in the laser, while in practical laser systems it is common for the diameter to vary with position. A model for lasers with focusing-beam field variations is developed here. Linear stability analysis shows that higher values of excitation are required to reach the type 1 instability threshold for lasers with longitudinal variations of the beam diameter than for the uniform plane-wave laser model. Close

• 10. [Article] Waterfall Lasers

  Laser concepts can be applied to a broad range of physical phenomena. One of the closest parallels occurs with the fluttering oscillations that are sometimes observed in the falling sheets of water associated ...

  Citation × Citation Citation Abstract Copy Title: Waterfall Lasers Author: Casperson, Lee W. Year: 1997 Laser concepts can be applied to a broad range of physical phenomena. One of the closest parallels occurs with the fluttering oscillations that are sometimes observed in the falling sheets of water associated with fountains, dams, and natural waterfalls. In many respects these fluid feedback oscillations are similar to the electromagnetic modes of typical lasers, and recognition of this similarity led to the interpretation of the waterfall behavior. Gain profiles for the waterfall oscillations are developed, and the relationship of experimental waterfall data to the laser-like models is considered in detail. Title: Waterfall Lasers Author: Casperson, Lee W. Year: 1997 Laser concepts can be applied to a broad range of physical phenomena. One of the closest parallels occurs with the fluttering oscillations that are sometimes observed in the falling sheets of water associated with fountains, dams, and natural waterfalls. In many respects these fluid feedback oscillations are similar to the electromagnetic modes of typical lasers, and recognition of this similarity led to the interpretation of the waterfall behavior. Gain profiles for the waterfall oscillations are developed, and the relationship of experimental waterfall data to the laser-like models is considered in detail. Close