Green electron‐beam pumped laser arrays based on II–VI nanostructures

Abstract

Room temperature electron-beam pumped (U ¼ 15-26 keV) green lasers and laser arrays based on multiple quantum well II-VI structures with an extended up to 2 mm waveguide have been studied. The maximum achieved output pulse power is as high as 31 and 630 W per facet from a single 0.24-mm-wide laser element at the cavity length of 0.4 mm and a laser array consisting of 26 elements, respectively. 1 Introduction Electron-beam pumped (EBP) green semiconductor lasers based on undoped II-VI-based structures can be used for numerous applications, such as projection television, optical navigation, location systems, medicine, etc. Sufficient progress in the development of EBP lasers has been achieved using semiconductor heterostructures as the laser active elements instead of bulk materials [1]. The minimum value of the room temperature (RT) threshold current density in electron beam, achieved in a transverse pumping geometry for ZnSe-based separate confinement heterostructure lasers with the active region based on single CdSe quantum dot (QD) sheets, has been recently reported to be as low as 0.4-0.5 A/cm 2 at the electron energy of 8-9 keV [2]. Multiple quantum well (MQW) laser structures with the similar design of each active layers demonstrated the quantum efficiency up to 8.5% and the peak output pulsed power of 12 W per facet at RT [3]. To increase the peak output power one can use both the larger laser active region, e.g. an extended MQW waveguide, and the multielement laser array. This paper reports on design and studies of MQW ZnSe-based lasers and laser arrays pumped by a pulsed electron beam. We have used a homemade electron gun with the maximum total current of an electron beam as high as 600 mA at the electron energy below 26 keV. In contrast to our previous studies [1,2], this gun enables one to pump the laser array of several

Molecular beam epitaxy of ZnSSe/CdSe short-period superlattices for III–V/II–VI multijunction solar cells

“…The average vertical lattice constant of the SL was determined as follows: (4) where (5) Taking into account that, according to the PL data, = 1.3 ML, we find that, for the barrier layers in structure 1 371, x ≈ 0.34 and ≈ 4.3 ML. The obtained S content in the SL barrier layers is also in good agreement with the value determined from the RHEED intensity oscillations (see Table 2).…”

“…In recent years, work on the molecular beam epit axy (MBE) of wide gap II-VI semiconductors has mainly been aimed at the development of light emit ters for the green [1][2][3][4][5] and yellow-green [6] spectral ranges (laser [1,2,6] and LED [3] converters and electron beam pumped lasers [4,5]). Also, studies on the development and fabrication of yellow-green laser diodes based on Be containing II-VI compounds have been resumed.…”

Изменение структуры и люминесцентных свойств пленок ZnSe и ZnCdSe при облучении электронным пучком

“…В связи с этим, повышенное внимание уделялось разработке альтернативных путей получения лазерной генерации, не требующих p−n-перехода и омических контактов, а именно созданию сине-зеленых полупроводниковых лазерных конвертеров А 2 В 6 /A 3 N [3,4]) и полупроводниковых лазеров А 2 В 6 с электронно-лучевой накачкой (ПЛЭН) [5]. В последних исследованиях значения рабочей энергии электронов, требуемой для их работы при комнатной температуре были снижены до 4−10 keV, была получена генерация при рекордно низких значениях пороговой плотности тока пучка электронов -около 0.5 A/cm 2 [6], а использование лазерной сборки позволило получить импульсы излучения мощностью более 600 W [7]. Была продемонстрирована возможность работы ПЛЭН в течение нескольких часов без уменьшения выходной мощности, и показано, что, по всей видимости, именно количество дефектов в исходной гетероструктуре является фактором, определяющим срок службы лазеров [8].…”

AlGaN/GaN asymmetric graded-index separate confinement heterostructures designed for electron-beam pumped UV lasers

“…Its advantages include higher flexibility in the choice of materials for the active medium due to the absence of doping or electrical contacts, as well as higher radiative recombination efficiency since the electrons and holes generated by impact ionization share the same distribution in the active medium. This technology has allowed the fabrication of ZnSebased pulsed lasers that emit up to 600 W at 535 nm [12]. There are some studies of electron beam pumped AlGaN for the implementation of UV lamps [13][14][15][16][17][18][19][20].…”