Stable low-loss single-mode couplers

Loss and spectral control in fused tapered couplers

“…This refractive index change can be related to a change in the coupled power through Eq. (11) or (12). Silica glass has a positive dn/dT, and thus coupling decreases on heating as is found by experiment.…”

“…Equations (1 1) and (12) and the observation that the half period varies with waist dimension, are successful in modeling the gross features of coupler behavior, such as the increase of the coupling coefficient with increasing wavelength and with decreasing waist dimension. Indeed, these equations can even be generalized to describe polarization behavior."…”

“…In this paper, the SR is expressed as a percentage and is defined by (12) SR=ppX100% (16) where P and P are the powers measured on the output ports; Pt is the power remaining in the throughput fiber, and P is the power coupled to the second fiber.…”

Propagating-beam model for a single-mode-fibre fused coupler

“…1, consists of two monomode fibres melted together General structure of fused coupler position of cores during a fusing-and-pulling process as described in Reference 2 (the fibres can also be initially etched). Many aspects of operation of the single-mode-fibre couplers have been analysed already, both theoretically [3][4][5][6][7][8][9][10][11] and experimentally [1,2,4,5,8,[12][13][14][15]. The cornPaper 523OJ (El3), first received 22nd July and in revised form 22nd December 1986 The authors are with the Electromagnetism and Acoustics Laboratory, Gent University, Sint-Pietersnieuwstraat 41, B-9000 Gent, Belgium plexity of these devices is reflected by a variety of existing theoretical models, employing, for example, variational analysis [7], a finite-element method [10] and coupledmode theory [3][4][5][6].…”

The influence of external refractive index on transmission properties in fused single-mode fiber couplers

“…This technique is relatively simple in comparison to mechanical [4] or chemical polishing [5] techniques. Fused biconical single-mode couplers can be made with a low excess loss and arbitrary coupling coefficient [1] [2] [3] [6] [7].…”