Mark yeo university of michigan physics 442 advanced labs february 28, 2005 note. Laser pumping is the act of energy transfer from an external source into the gain medium of a laser. Options include wavelength locking and emission line narrowing. Multiphoton absorption in optical pumping of rubidium arxiv. Opticalpumping noise in laserpumped, alloptical microwave frequency references j. Compact diodepumped solidstate lasers dpssl are continuously replacing traditional gas lasers as well as enabling completely new technology. Optical pumping of rubidium advanced laboratory, physics 407 university of wisconsin madison, wi 53706 abstract a rubidium highfrequency lamp is used as the pumping light source to excite rubidium atoms in a sample cell. Proceedings of the 14th international conference on lasers 91. Ylf laser system based on a master oscillator power amplifier mopa configuration. Three and fourlevel systems excerpt from field guide to lasers in a simple twolevel system, it is not possible to obtain a population inversion with optical pumping because the system can absorb pump light i. We report an injectionseeded, all diodepumped highenergy nd. Lumentum fibercoupled diode lasers enable reliable, lowercost, and robust fiber laser design alternatives across all types of power levels. Akela offers fibercoupled and freespace modules for optical pumping of these lasers.
The observation of the characteristics of the light absorbed or reemitted by these atoms gives a lot of information about atomic structure, relaxation phenomena, interaction processes between atoms and photons. Hollberg time and frequency division, the national institute of standards and technology, m. Because of their excellent reliability, diode lasers from lumentum are ideally suited for use in solidstate laser and fiberlaser pumping. The relations between the output power of optically an pumped fir laser and the pumping power were studied theoretically by solving the density matrix equation of a fourlevel system by means of the matrix signal flow graph method. Commercially available diode arrays, while compact and inexpensive, have. Optical pumping is a method for transferring to an ensemble of atoms a fraction of the angular momentum carried by a beam of polarized resonance radiation 1. The pumps are now being sampled by customers and will be available in volume production later this year.
In this experiment you will explore the phenomenon of optical pumping and its application to fundamental measurements in atomic and nuclear physics with equipment originally. Complete the following before your experiments scheduled start date. The beat frequencies resulting between the pumping and probe lasers and a third laser reference laser are shown. Kastler who was awarded the nobel prize for this in 1966. The optical pumping process in an insulating solidstate laser can be illustrated schematically with reference to fig. The origin of this polarization is a transfer of populations between the magnetic sublevels by subsequent cycles of light absorption and emission. Optical pumping is important to a wide variety of applications from the laser, to precise measurements of atomic hyper. It is commonly used in laser construction, to pump the active laser medium so as to achieve population inversion. The aim of this thesis was therefore to investigate novel laser designs for given applications considering these. The complex behavior of hbrlaser pulse intensity, duration and time delay on the gas pressure was analyzed. A high electricaltooptical efficiency of the pump source of the order of 50% leads to a high overall power efficiency wallplug efficiency of the laser. In single tem 00 mode operation the co 2 laser, incorporating a ribbed tube with an active discharge length of 2. Black september 27, 2004 sometimes you want to magnetize a gas, to align all of the little magnetic moments of the gas atoms in the same direction. Optical pumping of rubidium university of san diego.
Optical pumping, in physics, the use of light energy to raise the atoms of a system from one energy level to another. A new generation of diodepumped solidstate lasers has been developed that enables ultrastable ti. Nonlinear effects in weak magnetic field conference paper pdf available in ieee journal of quantum electronics qe 86. When the number of particles in one excited state exceeds the number of particles in the ground state or a lessexcited state, population inversion is achieved. While early experiments on optical pumping of molecules 5.
Pdf nonlinear effects in optical pumping with lasers. However, compact and cost efficient designs are required to satisfy enduser demands. Electronic configuration in the standard notation is 1s22s22p63s23d104s24p65s. There are three levels in which population inversion takes place, those are 1. Techniques of optical pumping are also used outside the area of laser physics, often in fundamental research. A device used to excite atoms for stimulated emission in the production or amplification of laser signals, as in inducing stimulated emission in a laser. By excitation of the lasing atoms or molecules this is called pumping.
Specifically, the pump wavelength merely needs to be shorter than the band gap of the semiconductor laser in opsl, whereas a dpss laser needs to have the pump laser matched to the specific gain medium. Sequential optical pumping of a farinfrared ammonia laser. We presented cesium spectra using optical pumping spectroscopy with counterpropagating beams, as well as the dispersionlike signals and their use in the frequency stabilization of a laser diode pumping laser. Optical pumping is a process in which light energy is used to excite electrons from a lower to higher energy level. The energy is absorbed in the medium, producing excited states in its atoms. The pumping source light is filtered to transmit the d1 rb line and polarizers are used to produce circular polarization. In this condition, the mechanism of stimulated emission. The development of xefc a lasers by optical pumping in northwest institute of nuclear technology during recent 10 years is described in this paper. Energy conversion efficiency of 2% was achieved at p10 torr.
Rp photonics encyclopedia diodepumped lasers, dpss. Laser pumping synonyms, laser pumping pronunciation, laser pumping translation, english dictionary definition of laser pumping. A system may consist of atoms having a random orientation of their individual magnetic fields. When optically pumped, the atoms will undergo a realignment of individual magnetic fields with respect to the direction of the light beam. Optical pumping california institute of technology. It was first developed by alfred kastler in the early 1950s. New hbrlaser with resonant optical pumping by dflaser. High power diode lasers are at the heart of almost every solid state, alkali, and fiber laser systems.
Xray amplifier energy deposition scaling with channeled propagation pdf. Theoretical and experimental studies of optically pumped molecular. The spin of an electron is a natural twolevel system for realizing a quantum bit in the solid state 1,2,3,4,5,6,7,8,9,10,11,12,14,15,16. Introduction optical pumping 123 is a process used in high frequency spectroscopy, developed by a. In many cases, certain selection rules play a vital role, which reflect principles like the conservation of angular momentum. Optical pumping is a process in which light is used to raise or pump electrons from a lower energy level in an atom or molecule to a higher one. Laser pumping definition of laser pumping by the free. Its nuclear properties are different from hydrogen, however, and this will give it a di erent energylevel structure. It is commonly used in laser construction, to pump the active laser medium so. For an electron trapped in a semiconductor quantum dot. Optical pumping the transition rules for the 5s rb electron are similar to those for the simpli.
Optical pumping of rubidium adam egbert,1, a will wiegand,1 and hannah sheppard2 1university of san diego 2university of san diego dated. Laser frequency stabilization using fm optical pumping. When a sample of gaseous atoms is placed in a static magnetic eld, the electronic states undergo zeeman splitting in addition to nestructure and hyper ne. Under special conditions it is also possible to achieve inversion for a short time in a twolevel system, if the pumping time is short compared to all relaxation times of the system and even shorter than the rabi oscillation time t r. As a consequence, small power supplies are needed, and both the electricity consumption and the cooling demands are drastically reduced, compared with those for lamppumped lasers. Lasing at the use of offaxis pumping geometry pump radiation flounce of 0. For example, various methods of laser cooling essentially depend on optical pumping of atoms or ions, for example suspended in an optical trap. Practical applications of optical pumping include the maser, the laser, and very sensitive magnetometers. This paper presents a theoretical study of electrically pumped color center lasers, and demonstrates that it is pos sible to deliver enough electrical energy to a.
Laser pumping is the act of energy transfer from an external source into the gain medium of a. The laser is pumped at 941 or 968nm with laser diodes to provide the high brighness pumping needed to achieve gain. The gfactor and the lifetime of excited states could be determined from such experiments. Spinexchange optical pumping using a frequencynarrowed. Laser diode modules for optical pumping of solidstate. The 500mw uncooled pump has an sff 10pin butterfly package that can also be used in existing 14pin slots. Oclaro has expanded its pump portfolio with a new 500mw uncooled 980nm pump laser and a 2 x 600mw dual chip pump in a single package. These quantities are related through the spin exchange e.
Kastler discovered optical pumping in the 1950s and received the nobel prize for his work in 1966. Laser, pumping schemes, types of lasers and applications 1. While the opt video has been a great resource for the students helping them to quickly orient in the lab, it has become apparent that some common misconceptions regarding the experiment stem from some minor inconsistencies in the video. L379 a cesium beam atomic clock using laser optical pumping. Highbrightness diode laser modules for optical pumping of. The probe laser was a fibercoupled tunable diode laser with distributed feedback, operating near 912. The atoms used in this experiment are rubidium atoms. The magnetic resonances are measured as a function of rf power, the pumping time constants are measured experimentally, and the observation of. Electrical pumping of color center lasers university of rochester. You might plan to have somebody inhale the polarized gas, then look at the insides of their lungs using magneticresonance imaging, or you might want to investigate. Exact nonperturbative solutions are obtained by means of a fourier development of the response of the. A cesium beam atomic clock using laser optical pumping.
A joule level of xefca laser optically pumped by a sectioned surface discharge was studied with the total efficiency of 0. Why is two level laser impossible even with nonoptical. Twotint pumpprobe measurements using a femtosecond. Efficient and simple, pumping of the semiconductor gain medium is another advantage over other diodepumped laser types. Optical pumping and doubleresonance techniques springerlink.
Laser, pumping schemes, types of lasers and applications. Optically pumped molecular gas lasers based on vibrationalrotational transitions in. Laser power requirement of optical pumping and rate. The laser produces pulses with over 4 j of pulse energy at 10 hz, 527 nm, and pulse. When an atomic medium is irradiated with circularly or linearly polarized light that is resonant with a transition between states of angular momenta and the medium becomes spin polarized. The optical pumping of high j levels with a broadband cw laser is studied theoretically. The highlyintegrated and ultracompact 140 w and 200 w st. Laser light amplification by stimulated emission of radiation. The technique was developed by 1966 nobel prize winner alfred kastler in the early 1950s optical pumping is also used to cyclically. An external magnetic field causes zeeman effect, and creates sublevels based on the hyperfine splitting. Optical pumping is a method to explore the atomic structure of atoms. In this experiment, anomalous zeeman transitions in the ground state of. Rp photonics encyclopedia optical pumping, pump light.
969 345 350 1614 912 1561 479 1250 1261 461 872 1373 1260 628 1113 833 228 1340 1378 1484 1189 1511 770 1482 760 533 25 1084 1403 89 119 858 862 664 496 1397 1006 52