“…Baxter Q-operators for concrete physical models can be obtained by specifying representations of the Borel subalgebra. Much work has been done related to this 'q-oscillator construction' of Baxter Q-operators (see, for example, the following papers and references therein: [3,4,5,6,7,8,9,10,11,12,13,14,15,16,17] for the trigonometric case; [18,19,20,21] for the rational case; [22,23,24,25,26] for some other methods). Moreover, systematic studies related to this from the point of view of the asymptotic representation theory of quantum affine algebras were done in [27,28,29].…”