The spectrum of the multi-frequency quasi-periodic CMV matrices contains intervals

2025/02/24 by Zhang, Bei, Piao, Daxiong
#2010 37A30 #42C05 #70G60 #FOS: Mathematics #Spectral Theory (math.SP)

paper · doi:10.48550/arxiv.2502.17532

Abstract

We investigate the spectral structure of multi-frequency quasi-periodic CMV matrices with Verblunsky coefficients defined by shifts on the d-dimensional torus. Under the positive Lyapunov exponent regime and standard Diophantine frequency conditions, we establish that the spectrum of these operators contains intervals on the unit circle.

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