Provided are chromophores with very large two-photon absorption cross-sections. One group of these chromophores has the formula: (T—Q)n—N—Phm wherein Q is a single bond or 1,4-phenylene, Ph is a phenyl group, n has a value of 1-3 and m has a value of 3−n, and wherein T is wherein R1 and R2 are alkyl groups having 1 to 20 carbon atoms, provided that when Q is a single bond, the value of n is 2 or 3. Another group of these chromophores has the formula: (T—Q)n—G—Phm wherein T is as defined above, Q is a single bond or 1,4-phenylene, Ph is a phenyl group, n has a value of 1-4 and m has a value of 4−n, and wherein G is a 4-arm core unit. Yet another group of these chromophores has the formula: (T—Q)n—G—Phm wherein T is as described previously, Q is a single bond or 1,4-phenylene, Ph is a phenyl group, n has a value of 1-6 and m has a value of 6−n, and wherein G is a 6-arm core unit.