Ultrahigh resolution long range surface plasmon-based sensor

An ultra-high sensitive surface plasmon resonance (SPR) sensor based on excitation of a long range surface plasmon was developed. Compared to previous reports, the sensor employs more advanced photonic components like superluminescent diode source and polarization-maintaining fibers, which allowed for dramatic decrease of the sensor detection limit. The attained refractive index detection limit of 2.5 × 10−8 is so far the highest value reported for any SPR-based sensor.