Controlled atomic spontaneous emission fromEr3+in a transparent Si/SiO2

Abstract

The spontaneous emission lifetime and intensity of Er implanted into SiC>2 is modified by a Si/SiC>2 planar microcavity. The cavity strongly affects the coupling of the optically excited Er 3+ to the radiative and waveguiding modes of the system, resulting in a spontaneous lifetime of 14.8 ms for a cavity offresonance with the Er 3+ versus a lifetime of 9.1 ms for an on-resonance cavity. The observed spontaneous emission lifetime changes agree well with calculated values based on a computation method which is also presented. 32.70.Fw, 32.70.Jz, 78.66.Jg There has been much recent attention regarding the use of planar microcavities to demonstrate fundamental changes in the spontaneous emission rates and spectra of emitting media. After cavity effects at radio frequencies were first proposed by Purcell [1] in 1946, other authors [2] have demonstrated that confocal resonators indeed can drastically modify the spontaneous emission lifetime of an atom within a resonator of millimeter wavelengths. This concept has been extended to short planar cavities at optical wavelengths, where experiments using flowing dye [3], dye-containing films [4], and semiconductors [5] as the active media have demonstrated significant lifetime changes. None of these experimental results in planar cavities, however, was quantitatively compared to theoretical models. Nonradiative energy loss processes, pump-dependent spectra, and the effects of selfabsorption of emitted light by the active media [6] can affect the measured lifetimes. In our experiment, we measure the spontaneous lifetime changes of the A J\V2~^ 4^1 5/2 transition of Er 3+ ions (emission wavelength -1535 nm) implanted at low concentration into a thin (half-wavelength) SiC>2 film, surrounded by highreflectivity Si/SiC>2 planar distributed Bragg reflectors. The Er 3+ ions exhibit atomic, intra-4/, electronic transitions which are effectively shielded by the outlying 5s 2 and 5/7 6 electrons, and the probed 4 713/2 -*^ 4^ 15/2 transition has a nearly 100% quantum efficiency [7]. This system is thus ideal for measuring cavity-induced lifetime changes because of the small self-absorption of the Er 3+ ions, and the narrow atomic emission spectrum. This enables us to compare, for the first time, active-media lifetimes for various thickness planar resonators with calculated values. These result from a general computation method which is also presented.The Er-doped SiC>2 active region (X/2) is -540 nm thick and is surrounded by distributed Bragg reflectors (DBRs), which are composed [8] of 4 (bottom) and 2 j pairs (top) of Si (115 nm) and SiC>2 (270 nm) quarterwave layers, e-beam deposited on a Si substrate. The calculated bottom and top mirror reflectivities (Rbot and /?top) are 99.8% and 98.5%, respectively. Implantation of 800 keV, 1 x 10 15 Er + /cm 2 into the active region was performed prior to deposition of the top DBR, in order to yield a sharp concentration profile (full width at half maximum -260 nm) just below the center plane of the active region. The Er concentration...

Broadband enhancement of light emission in silicon slot waveguides

“…concentration quenching) [9]. Therefore, increasing the spontaneous emission rate of Er [10,11] is important for improving luminescence efficiency or minimizing the effects of quenching processes, possibly allowing for a higher doping density.…”

Controlling fluorescence lifetime of rare-earth element in amorphous inorganic solids via very small compositional adjustments

“…Tailoring SER of a REE by positioning it inside appropriate periodic arrays of a dielectric surrounding is possible, although fabrication of such dielectric microstructures is usually not trivial. 7 In this respect, it is important to search for solid-state dielectrics doped with REE inside which the SER is very sensitive to changes of the nearest-neighboring atoms surrounding it. Control of the SER would then be possible in such doped dielectrics by way of adjusting external conditions such as temperature, pressure, and electric field.…”

Strong enhancement of spontaneous emission in amorphous-silicon-nitride photonic crystal based coupled-microcavity structures

“…42.70.Qs; 42.60.Da;78.66.Jg Ability to control spontaneous emission is expected to have practical importance in certain commercial applications. Thus, in the past decade, photonic band gap materials were proposed for alteration (inhibition and enhancement) of the spontaneous emission from atoms [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. …”