The Study on Gamma Ray Laser

Abstract

Similar to how a conventional laser produces coherent visible light rays, a hypothetical device called a gamma-ray laser, or graser, would produce coherent gamma rays.[22] Potential applications for gamma-ray lasers include medical imaging, spaceship propulsion, and cancer treatment.[23] In his Nobel lecture in 2003, Vitaly Ginzburg named the gamma-ray laser as one of the top 30 scientific problems.[24] Building a working gamma-ray laser is an interdisciplinary project that requires expertise and research in quantum mechanics, nuclear and optical spectroscopy, chemistry, solid-state physics, and metallurgy in addition to the production, moderation, and interaction of neutrons. The course covers both engineering technologies and basic science.[25]

Introduction

A laser (Light Amplification by Stimulated Emission of Radiation) is a device that emits coherent, highly focused light through optical amplification based on stimulated emission. The first working laser was created by Theodore Maiman in 1960, building on the theoretical work of Charles Townes and Arthur Schawlow.

Laser light has exceptional spatial coherence (narrow, focused beam) and temporal coherence (single frequency or ultrashort pulses), enabling applications such as cutting, welding, photolithography, fiber-optic communication, barcode scanners, printers, medical surgery, entertainment lighting, and military targeting. Blue and UV semiconductor lasers are also used in high-brightness lighting and automobile headlamps.

The precursor to the laser was the maser (Microwave Amplification by Stimulated Emission of Radiation). Devices operating above microwave frequencies are now called lasers, while microwave-range devices remain masers. The process of emitting coherent light is called “lasing.”

Historical Development

• 1916: Albert Einstein proposed the concept of stimulated emission.

• 1928: Rudolf Ladenburg first observed stimulated emission experimentally.

• 1953: Charles Townes built the first maser at microwave frequencies.

• 1958: Townes and Schawlow published the theory of the “optical maser.”

• 1950s–1970s: Legal disputes with Gordon Gould, who coined the word laser, resulted in shared patents.

• 1960: Maiman built the first ruby laser.

• 1960: Javan, Bennett, and Herriott produced the first He–Ne gas laser.

• 1962: Robert Hall developed the first semiconductor laser.

Early lasers were used for alignment, holography, and eye surgery. In the 1970s–80s, they entered daily life with grocery scanners, CD players, and laser printers. Today, lasers are used in science, engineering, medicine, space exploration, and communication.

Principle of Laser Operation

Atoms have discrete energy levels. When electrons drop from a higher to a lower level, they can emit photons via:

1. Spontaneous emission

2. Stimulated emission (core mechanism of lasers)

A laser requires a population inversion, where more atoms are in an excited state than in the ground state. This is achieved through pumping (light or electric current).

Laser types by energy levels:

• Three-level laser: uses ground, excited, and metastable states; usually pulsed (e.g., ruby laser).

• Four-level laser: adds one more level, enabling continuous operation.

Laser Components and Beam Characteristics

A typical laser system contains:

• Gain medium (gas, solid, or semiconductor)

• Pumping source

• Optical resonator (two mirrors)

Light bounces between mirrors, becoming more intense until a portion exits as a coherent beam.

Laser light is:

• Monochromatic (single wavelength)

• Highly collimated (narrow beam)

• Coherent (waves in phase)

Beam divergence depends on wavelength and aperture size. Some lasers produce continuous beams, while others generate extremely intense pulses as short as femtoseconds (10?¹? s).

Gamma-Ray Laser (Graser)

A gamma-ray laser would emit coherent gamma radiation, but it is still theoretical. Potential uses include:

• Cancer therapy

• Medical imaging

• Space propulsion

Challenges include:

• Achieving extremely high nuclear excitation densities

• Overcoming line broadening

• Preserving the Mössbauer effect

• Managing heating during neutron pumping

Several advanced concepts—such as two-stage neutron-gamma pumping and multi-level nuclear schemes—have been proposed, but no practical graser exists yet.

Conclusion

In summary, a device known as a gamma-ray laser, or graser, would generate coherent gamma rays in a manner similar to that of a normal laser, which creates coherent visible light rays.[22] Gamma-ray lasers have potential uses in cancer therapy, starship propulsion, and medical imaging.[23] Vitaly Ginzburg listed the gamma-ray laser as one of the top 30 scientific problems in his 2003 Nobel talk.[24] In addition to the production, moderation, and interaction of neutrons, the construction of a functional gamma-ray laser is an interdisciplinary endeavor that calls for knowledge and investigation in quantum mechanics, nuclear and optical spectroscopy, chemistry, solid-state physics, and metallurgy. Basic scientific and engineering technologies are both covered in the course.[25]

References

[1] Taylor, Nick (2000). Laser: The Inventor, The Nobel Laureate, and The Thirty-Year Patent War. Simon & Schuster. p. 66. ISBN 978-0684835150. [2] Ross T., Adam; Becker G., Daniel (2001). Proceedings of Laser Surgery: Advanced Characterization, Therapeutics, and Systems. SPIE. p. 396. ISBN 978-0-8194-3922-2. [3] \"December 1958: Invention of the Laser\". aps.org. Archived from the original on December 10, 2021. Retrieved January 27, 2022 [4] Semiconductor Sources: Laser plus phosphor emits white light without droop\". November 7, 2013. Archived from the original on June 13, 2016. Retrieved February 4, 2019. [5] Laser Lighting: White-light lasers challenge LEDs in directional lighting applications\". February 22, 2017. Archived from the original on February 7, 2019. Retrieved February 4, 2019. [6] How Laser-powered Headlights Work\". November 7, 2011. Archived from the original on November 16, 2011. Retrieved February 4, 2019. [7] Laser light for headlights: Latest trend in car lighting | OSRAM Automotive\". Archived from the original on February 7, 2019. Retrieved February 4, 2019. [8] Heilbron, John L. (March 27, 2003). The Oxford Companion to the History of Modern Science. Oxford University Press. pp. 447. ISBN 978-0-19-974376-6. [9] Bertolotti, Mario (October 1, 2004). The History of the Laser. CRC Press. pp. 215, 218–219. ISBN 978-1-4200-3340-3. [10] McAulay, Alastair D. (May 31, 2011). Military Laser Technology for Defense: Technology for Revolutionizing 21st Century Warfare. John Wiley & Sons. p. 127. ISBN 978-0-470-25560-5. [11] Renk, Karl F. (February 9, 2012). Basics of Laser Physics: For Students of Science and Engineering. Springer Science & Business Media. p. 4. ISBN 978-3-642-23565-8. [12] LASE\". Collins Dictionary. Retrieved January 6, 2024. [13] \"LASING\". Collins Dictionary. Retrieved January 6, 2024. [14] Strelnitski, Vladimir (1997). \"Masers, Lasers and the Interstellar Medium\". Astrophysics and Space Science. 252: 279–287. Bibcode:1997Ap&SS.252..279S. doi:10.1023/ [15] Chu, Steven; Townes, Charles (2003). \"Arthur Schawlow\". In Edward P. Lazear (ed.). Biographical Memoirs. Vol. 83. National Academy of Sciences. p. 202. ISBN 978-0-309-08699-8 [16] Al-Amri, Mohammad D.; El-Gomati, Mohamed; Zubairy, M. Suhail (December 12, 2016). Optics in Our Time. Springer. p. 76. ISBN 978-3-319-31903-2. [17] Hecht, Jeff (December 27, 2018). Understanding Lasers: An Entry-Level Guide. John Wiley & Sons. p. 201. ISBN 978-1-119-31064-8. [18] https://www.ulsinc.com/learn [19] https://www.fiberoptics4sale.com/blogs/wave-optics/semiconductor-laser-physics [20] https://www.szlaser.com/index.php/wiki/laser-physics/ [21] https://www.britannica.com/technology/laser [22] Baldwin, G. C. (1979). \"Bibliography of GRASER research\". Los Alamos Scientific Laboratory Report LA-7783-MS. doi:10.2172/6165356. OSTI 6165356 [23] Pittalwala, Iqbal (2019-12-05). \"Gamma-ray laser moves a step closer to reality\". University of California, Riverside. Retrieved 2022-11-27. [24] Ginzburg, V. L. (2003). \"On superconductivity and superfluidity\". The Nobel Prize in Physics 2003: 96–127. [25] Baldwin, G. C.; Solem, J. C.; Gol\'danskii, V. I. (1981). \"Approaches to the development of gamma-ray lasers\". Reviews of Modern Physics. 53 (4): 687–744. Bibcode:1981RvMP...53..687B. doi:10.1103/revmodphys.53.687 [26] Baldwin, G. C.; Solem, J. C. (December 1979). \"The Direct Pumping of Gamma-Ray Lasers by Neutron Capture\". Nuclear Science and Engineering. 72 (3): 290–292. Bibcode:1979NSE....72..290B. doi:10.13182/NSE79-A20385 [27] Vali, V.; Vali, W. (1963). \"Induced gamma y-ray emission\". Proceedings of the IEEE. 51 (1): 182–184. Bibcode:1963IEEEP..51..182V. doi:10.1109/proc.1963.1677 [28] Letokhov, V. S. (1973). \"On the problem of the nuclear-transition gamma-laser\". Journal of Experimental and Theoretical Physics. 37 (5): 787–793. Bibcode:1973JETP...37..787L [29] Kamenov, P.; Bonchev, T. (1975). \"On the possibility of realizing a gamma laser with long-living isomer nuclei\". BolgarskaiaAkademiiaNauk, Doklady. 28 (9): 1175–1177. Bibcode:1975BlDok..28.1175K [30] Il\'inskii, Yu. A.; Khokhlov, R. V. (1976). \"Possibility of creating a gamma-laser\". Radiophysics and Quantum Electronics. 19 (6): 561–567. Bibcode:1976R&QE...19..561I. doi:10.1007/bf01043541. S2CID 120340405 [31] Baldwin, G. C. (1977). \"On the Feasibility of Grasers\". Laser Interaction and Related Plasma Phenomena. Vol. 4A. Boston, MA: Springer. pp. 249–257. doi:10.1007/978-1-4684-8103-7_13. ISBN 978-1-4684-8105-1. [32] Terhune, I. H.; Baldwin, G. C. (1965). \"Nuclear superradiance in solids\". Physical Review Letters. 14 (15): 589–591. Bibcode:1965PhRvL..14..589T. doi:10.1103/physrevlett.14.589 [33] Baldwin, G. C. (1974). \"Is There a High Frequency Limit to Laser Action?\". Laser Interaction and Related Plasma Phenomena. Vol. 3B. pp. 875–888. doi:10.1007/978-1-4684-8416-8_23. ISBN 978-1-4684-8418-2. [34] Andreev, A V.; Il\'inskii, Yu. A. (1975). \"Amplification in a gamma laser when the Bragg condition is satisfied\". Journal of Experimental and Theoretical Physics. 41 (3): 403–405. Bibcode:1975JETP...41..403A [35] Il\'inskii, Yu. A.; Khokhlov, R. V. (1974). \"On the possibility of observation of stimulated gamma radiation\". Soviet Physics Uspekhi. 16 (4): 565–567. doi:10.1070/pu1974v016n04abeh005306 [36] Baldwin, G. C.; Solem, J. C. (1997). \"Recoilless gamma-ray lasers\". Reviews of Modern Physics. 69 (4): 1085–1117. Bibcode:1997RvMP...69.1085B. doi:10.1103/revmodphys.69.1085 [37] Borrmann, G. (1941). \"ÜberExtinktionsdiagramme der Röntgenstrahlen von Quarz\". PhysikalischeZeitschrift. 42: 157–162. [38] Kagan, Yu. M. (1974). \"Use of the anomalous passage effect to obtain stimulated emission of gamma quanta in a crystal\". JETP Letters. 20 (1): 11–12. Bibcode:1974JETPL..20...11K [39] Andreev, A. V.; Il\'inskii, Yu. A. (1976). \"Possible use of the Borrmann effect in the gamma laser\". Journal of Experimental and Theoretical Physics. 43 (5): 893–896. Bibcode:1976JETP...43..893A [40] Baldwin, G. C.; Solem, J. C. (1979). \"Maximum density and capture rates of neutrons moderated from a pulsed source\". Nuclear Science and Engineering. 72 (3): 281–289. Bibcode:1979NSE....72..281B. doi:10.13182/NSE79-A20384 [41] Baldwin, G. C.; Solem, J. C. (1995). \"Kinetics of neutron-burst pumped gamma-ray lasers\". Laser Physics. 5 (2): 326–335. [42] Gol\'danskii, V. I.; Kagan, Yu.; Namiot, V. A. (1973). \"Two-stage pumping of Mössbauer gamma-ray lasers\". JETP Letters. 18 (1): 34–35. Archived from the original on 2016-03-06. Retrieved 2016-02-24. [43] Gol\'danskii, V. I.; Kagan, Yu. (1973). \"The possibility of creating a nuclear gamma laser\". Journal of Experimental and Theoretical Physics. 37 (1): 49. Bibcode:1973JETP...37...49G [44] Baldwin, G. C.; Solem, J. C. (1980). \"Two-stage pumping of three-level Mössbauer gamma-ray lasers\". Journal of Applied Physics. 51 (5): 2372–2380. Bibcode:1980JAP....51.2372B. doi:10.1063/1.328007 [45] Baldwin, G. C. (1984). \"Multistep Pumping Schemes for Short-Wave Lasers\". Laser Interaction and Related Plasma Phenomena. Vol. 6. pp. 107–125. doi:10.1007/978-1-4615-7332-6_8. ISBN 978-1-4615-7334-0. [46] Solem, J. C.; Biedenharn, L. C. (1987). \"Primer on coupling collective electronic oscillations to nuclei\" (PDF). Los Alamos National Laboratory Report LA-10878. Bibcode:1987pcce.rept. [47] Biedeharn, L. C.; Baldwin, G. C.; Boer, K. (1986). Nuclear excitation by laser driven coherent outer shell electron oscillations. Proceedings of the First International Laser Science Conference, Dallas, TX, November 18–22, 1985. Stwalley, W. C.; Lapp, M.; Eds. Vol. 146. pp. 52–53. Bibcode:1986AIPC..146...52B. doi:10.1063/1.35933 [48] Solem, J. C.; Biedenharn, L. C.; Rinker, G. A. (1987). \"Calculation of harmonic radiation from atoms subjected to strong laser fields and the possibility of nuclear excitation\". Annual Meeting Optical Society of America. pp. TUS6. doi:10.1364/OAM.1987.TUS6 [49] Solem, J. C.; Biedenharn, L. C. (1988). \"Laser coupling to nuclei via collective electronic oscillations: A simple heuristic model study\". Journal of Quantitative Spectroscopy and Radiative Transfer. 40 (6): 707–712. Bibcode:1988JQSRT..40..707S. doi:10.1016/0022-4073(88)90066-0 [50] Solem, J. C. (1988). \"Theorem relating spatial and temporal harmonics for nuclear interlevel transfer driven by collective electronic oscillation\". Journal of Quantitative Spectroscopy and Radiative Transfer. 40 (6): 713–715. Bibcode:1988JQSRT..40..713S. doi:10.1016/0022-4073(88)90067-2

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Copyright © 2025 Muhammad Arif Bin Jalil. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.