Swiss roll is a type of optical metamaterial that has negative refractive index. It is named for its resemblance to the confectionery swiss roll: it consists of concentric cylinders of insulated metal.

Swiss roll is a type of sponge cake baked in a very shallow rectangular baking tray, and then filled, rolled up, and served in circular slices. In most cases, it is rolled up in a clean tea towel as soon as it comes out of the oven, while it is still flexible enough to roll without cracking. It is left to cool in this shape, then unrolled, filled with jam, jelly, lemon curd, or other filling, and then rolled up again.