An optical switching system disposed on a substrate that defines a first plane (P1), the optical switching system comprising a first switching cell (102-1-1) that includes: a first bus waveguide (202-1) having a first input (IP1-1-1) and a first output (OP1-1-1), wherein the first bus waveguide is dimensioned and arranged to support propagation of a first light signal comprising both transverse-electric (TE) and transverse-magnetic (TM) polarization modes, and wherein the first bus waveguide resides in a second plane (P2) that is parallel with the first plane; a second bus waveguide (202-2) having a second output (OP2-1-1), wherein the second bus waveguide is dimensioned and arranged to support propagation of the first light signal, and wherein the second bus waveguide resides in a third plane (P3) that is parallel with the first plane, the second and third planes being separated by a first separation (d1); a first shunt waveguide (204-1) that is movable with respect to the substrate, wherein the first shunt waveguide is dimensioned and arranged to support propagation of the first light signal; and a first actuator that is operative for moving the first shunt waveguide between the first and second positions; wherein, when the first shunt waveguide is in a first position; the first shunt waveguide is optically decoupled from each of the first and second bus waveguides, and the first input is optically coupled with the first output and substantially optically decoupled from the second output; wherein, when the first shunt waveguide is in a second position; the first shunt waveguide is optically coupled with the first and second bus waveguides, and the first input is substantially optically decoupled from the first output and optically coupled with the second output through the first shunt waveguide; and wherein each of the first bus waveguide and the second bus waveguide is dimensioned and arranged such that each of the TE- and TM-polarization modes of the first light signal is characterized by group velocities that are equal within 10%. a first bus waveguide (202-1) having a first input (IP1-1-1) and a first output (OP1-1-1), wherein the first bus waveguide is dimensioned and arranged to support propagation of a first light signal comprising both transverse-electric (TE) and transverse-magnetic (TM) polarization modes, and wherein the first bus waveguide resides in a second plane (P2) that is parallel with the first plane; a second bus waveguide (202-2) having a second output (OP2-1-1), wherein the second bus waveguide is dimensioned and arranged to support propagation of the first light signal, and wherein the second bus waveguide resides in a third plane (P3) that is parallel with the first plane, the second and third planes being separated by a first separation (d1); a first shunt waveguide (204-1) that is movable with respect to the substrate, wherein the first shunt waveguide is dimensioned and arranged to support propagation of the first light signal; and a first actuator that is operative for moving the first shunt waveguide between the first and second positions; wherein, when the first shunt waveguide is in a first position; the first shunt waveguide is optically decoupled from each of the first and second bus waveguides, and the first input is optically coupled with the first output and substantially optically decoupled from the second output; wherein, when the first shunt waveguide is in a second position; the first shunt waveguide is optically coupled with the first and second bus waveguides, and the first input is substantially optically decoupled from the first output and optically coupled with the second output through the first shunt waveguide; and wherein each of the first bus waveguide and the second bus waveguide is dimensioned and arranged such that each of the TE- and TM-polarization modes of the first light signal is characterized by group velocities that are equal within 10%. <EOS>