A heat assisted magnetic recording (HAMR) head has a near-field transducer (NFT) with a distal end having a leading side taper inclined at an acute angle to the ABS, such that an acute angle is formed between a leading surface of the leading side taper and the ABS. A main magnetic pole is disposed in the head facing a trailing side of the NFT. A waveguide core layer is disposed in the head facing the leading side taper of the NFT, on which a high refractive index material (HRIM) layer is positioned.