QHack QML Challenge Walkthrough: Variational Quantum Eigensolver


Category: qhack | Author: Olivia Di Matteo (PennyLane Team)
QHack 2021, the quantum machine learning (QML) hackathon, ran earlier this year from 17-26 February. A big portion of the event was the QML Challenge Leaderboard, where hundreds of teams raced to solve QML programming problems in order to claim hardware credits to help with their Open Hackathon projects. Solutions …

IonQ’s trapped ion hardware now available via PennyLane


Category: plugins | Author: PennyLane Team
We are excited to announce that PennyLane now natively supports quantum computing devices provided by IonQ! 🎉🍾 IonQ is the leading provider of quantum computers based on trapped ions. With long coherence times and all-to-all connectivity, trapped ions make a great hardware substrate for testing complex quantum computing algorithms, like those …

PennyLane v0.15 released


Category: release | Author: PennyLane team
We’re excited to announce PennyLane v0.15, which comes with many new and exciting features. These include a new hardware device integration, more flexible shot control, brand new operations, and new methods for working with more powerful quantum circuits.

How to build a model with chained QNodes


Category: how-to | Author: Josh Izaac (PennyLane team)
In PennyLane, we can easily construct VQE and QAOA-like models. However, the flexibility of PennyLane allows much more interesting models to be constructed. In this how-to, we’ll show you how to chain two QNodes together.

How to calculate the Hessian of a classical-quantum hybrid model


Category: how-to | Author: Josh Izaac (PennyLane Team)
PennyLane QNodes don’t just support computing the derivative—they also support computing the second derivative. Further, the second derivative can be computed on both simulators and quantum hardware. In this how-to, we’ll show you how you can extract the Hessian of a hybrid model using PennyLane in three …