Narrow Results

A symmetry broken hexagram metamaterial (SBHM) is presented to enhance the polarization sensitivity, and thus realize mechanically controlling the transmissions of tri-band in terahertz (THz) region. This SBHM has different electromagnetic response for rotating clockwise and anticlockwise, respectively. When incident THz wave is polarized in the direction of $\phi =0^{\circ }$, the SBHM has three stopbands with central frequencies at 0.36 THz, 0.52 THz and 0.75 THz, respectively. When the SBHM rotates clockwise $(\phi >0^{\circ })$, the transmission of 0.52 THz increases from 0.17 to 0.85, and its modulation depth reaches 68%. On the contrary, when it rotates anticlockwise $(\phi <0^{\circ })$, the transmissions of the other two bands can be modulated simultaneously, and their modulation depth are 78% and 40%, respectively. The physical mechanism for the tunability is investigated using finite-integration time-domain (FITD) method. The results indicated that the tri-band tunability in the SBHM is due to the mode transfer and polarization sensitivity enhancement which is induced by near field coupling. This novel design proves a new way for modulation, selection and switching of the THz wave at multiband.

This paper studies the Hirota–Maxwell–Bloch (H–MB) system and its nonlocal form. Based on the Darboux Transformations (DTs), for H–MB system, we present general double breathers, what is more, we take appropriate modulation frequency and position parameters to investigate the generative mechanism of rogue wave sequences and different periodic breather sequences. For nonlocal Hirota–Maxwell–Bloch (NH–MB) system, we discuss symmetry preserving and broken soliton solutions under zero background. Besides, we present nine combinations of dark and antidark soliton solutions under continuous waves background when PT-symmetry is broken.

In this paper, we explore domains in conjunction with the defined parametric space of function , which represents a N-body system in complex form. Interested observations on the computed results reveal limited levels of Herman ring fractals, symmetry broken, and transition to chaos based on phase parameter exp(g_i(z)) and a_i.